chore: embed original ReScript in .affine skeletons for easier porting (#57)

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SPDX-License-Identifier: CC-BY-SA-4.0
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## Summary

<!-- What does this PR do, and why? -->

Closes #

## Type of change

- [ ] 🐛 Bug fix (non-breaking change that fixes an issue)
- [ ] ✨ New feature (non-breaking change that adds functionality)
- [ ] 💥 Breaking change (would change existing behaviour)
- [ ] 🕳️ Soundness fix (fixes a checker/proof false-negative)
- [ ] 📖 Documentation
- [ ] 🧹 Refactor / tech debt (behaviour-preserving)
- [ ] ⚡ Performance
- [ ] 🔧 Build / CI / tooling

## How has this been verified?

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## Checklist

- [ ] My commits are **signed** (`git commit -S`).
- [ ] I ran the project's own checks/tests locally and they pass.
- [ ] New files carry the correct `SPDX-License-Identifier` (code/config
`MPL-2.0`,
      prose `CC-BY-SA-4.0`); I did not relicense existing files.
- [ ] Docs are updated, and no public claim now overstates what the code
does.
- [ ] I have not introduced a soundness hole (or I have flagged where I
might have).

## Notes for reviewers

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Author: hyperpolymath

src/App.affine

@@ -5,3 +5,37 @@
 module App;
 
 // TODO: Complete semantic implementation
+
+
+/* === ORIGINAL RESCRIPT IMPLEMENTATION ===
+// SPDX-License-Identifier: MPL-2.0
+// DotMatrix-FilePrinter - App module
+// Exports functions for the UI layer
+// Uses proven library for formally verified safety operations
+
+// Re-export bindings for JavaScript consumption
+let checkGforth = Bindings.checkGforth
+let previewStrike = Bindings.previewStrike
+let executeStrike = Bindings.executeStrike
+let verifySubstrate = Bindings.verifySubstrate
+
+// Utilities (powered by proven library)
+let stringToBytes = Bindings.stringToBytes
+let bytesToString = Bindings.bytesToString
+let parseByteString = Bindings.parseByteString
+let isValidByte = Bindings.isValidByte
+let isValidPath = Bindings.isValidPath
+let bytesToHex = Bindings.bytesToHex
+let bytesToHexCompact = Bindings.bytesToHexCompact
+let hexToBytes = Bindings.hexToBytes
+
+// For hex input mode
+let decodeHex = Bindings.hexToBytes
+
+// Constraint values for UI
+let maxByte = Types.Constraints.maxByte
+let forbiddenNbsp = Types.Constraints.forbiddenNbsp
+let forbiddenUtf8 = Types.Constraints.forbiddenUtf8
+let forbiddenBytes = Types.Constraints.forbiddenBytes
+
+======================================== */

src/Bindings.affine

@@ -5,3 +5,134 @@
 module Bindings;
 
 // TODO: Complete semantic implementation
+
+
+/* === ORIGINAL RESCRIPT IMPLEMENTATION ===
+// SPDX-License-Identifier: MPL-2.0
+// Backend FFI Bindings for DotMatrix-FilePrinter
+// Uses proven library for formally verified safety operations
+// Uses RuntimeBridge for Gossamer/Tauri/browser dispatch
+
+// Core backend API — delegates to RuntimeBridge for runtime detection
+let invoke = RuntimeBridge.invoke
+
+// Re-export types
+type contaminant = Types.contaminant
+type previewResult = Types.previewResult
+type verifyResult = Types.verifyResult
+
+// Commands - these call the Rust backend
+
+// Check if gforth is available
+let checkGforth = (): promise<bool> => {
+  invoke("check_gforth", ())
+}
+
+// Preview strike (dry-run)
+let previewStrike = (bytes: array<int>): promise<previewResult> => {
+  invoke("preview_forth_strike", {"bytes": bytes})
+}
+
+// Helper to create a rejected promise with an error message
+let rejectWithMessage: string => promise<'a> = %raw(`
+  function(msg) { return Promise.reject(new Error(msg)); }
+`)
+
+// Execute strike via Forth kernel (with path validation using SafePath)
+let executeStrike = (bytes: array<int>, path: string): promise<unit> => {
+  // Validate path doesn't contain traversal attacks
+  if !Proven_SafePath.isSafe(path) {
+    rejectWithMessage("Invalid path: contains traversal sequences")
+  } else {
+    invoke("execute_forth_strike", {"bytes": bytes, "path": path})
+  }
+}
+
+// Verify substrate file (with path validation using SafePath)
+let verifySubstrate = (path: string): promise<verifyResult> => {
+  if !Proven_SafePath.isSafe(path) {
+    rejectWithMessage("Invalid path: contains traversal sequences")
+  } else {
+    invoke("verify_substrate", {"path": path})
+  }
+}
+
+// Utilities using proven library
+
+// Convert string to byte array using SafeString.toCodePoints
+let stringToBytes = (str: string): array<int> => {
+  switch Proven_SafeString.toCodePoints(str) {
+  | Ok(bytes) => bytes
+  | Error(_) => []  // Return empty on non-ASCII input
+  }
+}
+
+// Convert byte array to string using SafeString.fromCodePoints
+let bytesToString = (bytes: array<int>): string => {
+  switch Proven_SafeString.fromCodePoints(bytes) {
+  | Ok(str) => str
+  | Error(_) => ""  // Return empty on invalid code points
+  }
+}
+
+// Validate a single byte (uses SafeMath via Types.Constraints)
+let isValidByte = (byte: int): bool => {
+  Types.Constraints.isValidByte(byte)
+}
+
+// Validate path safety using SafePath
+let isValidPath = (path: string): bool => {
+  Proven_SafePath.isSafe(path)
+}
+
+// Parse comma-separated bytes using SafeMath.fromString
+let parseByteString = (str: string): result<array<int>, string> => {
+  let parts = str
+    ->String.trim
+    ->String.split(",")
+    ->Array.map(String.trim)
+    ->Array.filter(s => s->String.length > 0)
+
+  // Use SafeMath.fromString for safe integer parsing
+  let bytes = parts->Array.map(s => Proven_SafeMath.fromString(s))
+
+  if bytes->Array.some(Option.isNone) {
+    Error("Invalid byte value")
+  } else {
+    let values = bytes->Array.filterMap(x => x)
+    let invalid = values->Array.findIndex(b => !isValidByte(b))
+    if invalid >= 0 {
+      Error(`Byte at position ${Int.toString(invalid)} is invalid`)
+    } else {
+      Ok(values)
+    }
+  }
+}
+
+// Format bytes as spaced hex using SafeHex.encodeSpaced
+let bytesToHex = (bytes: array<int>): string => {
+  switch Proven_SafeHex.encodeSpaced(bytes) {
+  | Ok(hex) => hex
+  | Error(_) => ""  // Return empty on invalid bytes
+  }
+}
+
+// Format bytes as compact hex (no spaces) using SafeHex.encode
+let bytesToHexCompact = (bytes: array<int>): string => {
+  switch Proven_SafeHex.encode(bytes) {
+  | Ok(hex) => hex
+  | Error(_) => ""
+  }
+}
+
+// Decode hex string to bytes using SafeHex.decode
+let hexToBytes = (hexStr: string): result<array<int>, string> => {
+  switch Proven_SafeHex.decode(hexStr) {
+  | Ok(bytes) => Ok(bytes)
+  | Error(Proven_SafeHex.InvalidLength) => Error("Invalid hex length (must be even)")
+  | Error(Proven_SafeHex.InvalidCharacter) => Error("Invalid hex character")
+  | Error(Proven_SafeHex.EmptyInput) => Ok([])
+  }
+}
+
+======================================== */

src/RuntimeBridge.affine

@@ -5,3 +5,215 @@
 module RuntimeBridge;
 
 // TODO: Complete semantic implementation
+
+
+/* === ORIGINAL RESCRIPT IMPLEMENTATION ===
+// SPDX-License-Identifier: MPL-2.0
+
+/// RuntimeBridge — Unified IPC bridge for DotMatrix-FilePrinter.
+///
+/// Detects the available runtime (Gossamer, Tauri, or browser-only) and
+/// dispatches `invoke` calls to the appropriate backend. This allows all
+/// command modules to use a single import instead of binding directly
+/// to `@tauri-apps/api/core`.
+///
+/// Priority order:
+///   1. Gossamer (`window.__gossamer_invoke`)  — own stack, preferred
+///   2. Tauri    (`window.__TAURI_INTERNALS__`) — legacy, transition
+///   3. Browser  (direct HTTP fetch)            — development fallback
+///
+/// Migration path: Bindings.res replaces
+///   `@module("@tauri-apps/api/core") external invoke: ...`
+/// with
+///   `let invoke = RuntimeBridge.invoke`
+
+// ---------------------------------------------------------------------------
+// Raw external bindings — exactly one of these will be available at runtime
+// ---------------------------------------------------------------------------
+
+/// Gossamer IPC: injected by gossamer_channel_open() into the webview.
+%%raw(`
+function isGossamerRuntime() {
+  return typeof window !== 'undefined'
+    && typeof window.__gossamer_invoke === 'function';
+}
+`)
+@val external isGossamerRuntime: unit => bool = "isGossamerRuntime"
+
+%%raw(`
+function gossamerInvoke(cmd, args) {
+  return window.__gossamer_invoke(cmd, args);
+}
+`)
+@val external gossamerInvoke: (string, 'a) => promise<'b> = "gossamerInvoke"
+
+/// Tauri IPC: injected by the Tauri runtime into the webview.
+%%raw(`
+function isTauriRuntime() {
+  return typeof window !== 'undefined'
+    && window.__TAURI_INTERNALS__ != null
+    && !window.__TAURI_INTERNALS__.__BROWSER_SHIM__;
+}
+`)
+@val external isTauriRuntime: unit => bool = "isTauriRuntime"
+
+@module("@tauri-apps/api/core")
+external tauriInvoke: (string, 'a) => promise<'b> = "invoke"
+
+// ---------------------------------------------------------------------------
+// Unified invoke — detects runtime and dispatches
+// ---------------------------------------------------------------------------
+
+/// The runtime currently in use. Cached after first detection for performance.
+type runtime =
+  | Gossamer
+  | Tauri
+  | BrowserOnly
+
+%%raw(`
+var _detectedRuntime = null;
+function detectRuntime() {
+  if (_detectedRuntime !== null) return _detectedRuntime;
+  if (typeof window !== 'undefined' && typeof window.__gossamer_invoke === 'function') {
+    _detectedRuntime = 'gossamer';
+  } else if (typeof window !== 'undefined' && window.__TAURI_INTERNALS__ != null && !window.__TAURI_INTERNALS__.__BROWSER_SHIM__) {
+    _detectedRuntime = 'tauri';
+  } else {
+    _detectedRuntime = 'browser';
+  }
+  return _detectedRuntime;
+}
+`)
+@val external detectRuntimeRaw: unit => string = "detectRuntime"
+
+/// Detect and return the current runtime.
+let detectRuntime = (): runtime => {
+  switch detectRuntimeRaw() {
+  | "gossamer" => Gossamer
+  | "tauri" => Tauri
+  | _ => BrowserOnly
+  }
+}
+
+/// Invoke a backend command through whatever runtime is available.
+///
+/// - On Gossamer: calls `window.__gossamer_invoke(cmd, args)`
+/// - On Tauri:    calls `window.__TAURI_INTERNALS__.invoke(cmd, args)`
+/// - On browser:  rejects with a descriptive error
+///
+/// This is the primary function all command modules should use.
+let invoke = (cmd: string, args: 'a): promise<'b> => {
+  if isGossamerRuntime() {
+    gossamerInvoke(cmd, args)
+  } else if isTauriRuntime() {
+    tauriInvoke(cmd, args)
+  } else {
+    Promise.reject(
+      JsError.throwWithMessage(
+        `No desktop runtime — "${cmd}" requires Gossamer or Tauri`,
+      ),
+    )
+  }
+}
+
+/// Check whether any desktop runtime is available.
+let hasDesktopRuntime = (): bool => {
+  isGossamerRuntime() || isTauriRuntime()
+}
+
+/// Get a human-readable name for the current runtime.
+let runtimeName = (): string => {
+  switch detectRuntime() {
+  | Gossamer => "Gossamer"
+  | Tauri => "Tauri"
+  | BrowserOnly => "Browser"
+  }
+}
+
+// ---------------------------------------------------------------------------
+// Dialog abstraction — Gossamer dialogs vs Tauri plugin-dialog
+// ---------------------------------------------------------------------------
+
+module Dialog = {
+  /// Gossamer file dialog: calls gossamer_dialog_open via IPC.
+  /// Tauri file dialog: calls @tauri-apps/plugin-dialog.
+  @module("@tauri-apps/plugin-dialog")
+  external tauriOpenRaw: JSON.t => promise<Nullable.t<JSON.t>> = "open"
+
+  @module("@tauri-apps/plugin-dialog")
+  external tauriSaveRaw: JSON.t => promise<Nullable.t<JSON.t>> = "save"
+
+  /// Open a file picker dialog.
+  let \"open" = (opts: JSON.t): promise<Nullable.t<JSON.t>> => {
+    if isGossamerRuntime() {
+      gossamerInvoke("__gossamer_dialog_open", opts)
+    } else if isTauriRuntime() {
+      tauriOpenRaw(opts)
+    } else {
+      Promise.reject(
+        JsError.throwWithMessage(
+          "No desktop runtime — file dialogs require Gossamer or Tauri",
+        ),
+      )
+    }
+  }
+
+  /// Open a save dialog.
+  let save = (opts: JSON.t): promise<Nullable.t<JSON.t>> => {
+    if isGossamerRuntime() {
+      gossamerInvoke("__gossamer_dialog_save", opts)
+    } else if isTauriRuntime() {
+      tauriSaveRaw(opts)
+    } else {
+      Promise.reject(
+        JsError.throwWithMessage(
+          "No desktop runtime — save dialogs require Gossamer or Tauri",
+        ),
+      )
+    }
+  }
+}
+
+// ---------------------------------------------------------------------------
+// Filesystem abstraction — Gossamer fs vs Tauri plugin-fs
+// ---------------------------------------------------------------------------
+
+module Fs = {
+  @module("@tauri-apps/plugin-fs")
+  external tauriReadTextFileRaw: string => promise<string> = "readTextFile"
+
+  @module("@tauri-apps/plugin-fs")
+  external tauriWriteTextFileRaw: (string, string) => promise<unit> = "writeTextFile"
+
+  /// Read a text file from the local filesystem.
+  let readTextFile = (path: string): promise<string> => {
+    if isGossamerRuntime() {
+      gossamerInvoke("__gossamer_fs_read_text", {"path": path})
+    } else if isTauriRuntime() {
+      tauriReadTextFileRaw(path)
+    } else {
+      Promise.reject(
+        JsError.throwWithMessage(
+          "No desktop runtime — filesystem access requires Gossamer or Tauri",
+        ),
+      )
+    }
+  }
+
+  /// Write a text file to the local filesystem.
+  let writeTextFile = (path: string, contents: string): promise<unit> => {
+    if isGossamerRuntime() {
+      gossamerInvoke("__gossamer_fs_write_text", {"path": path, "contents": contents})
+    } else if isTauriRuntime() {
+      tauriWriteTextFileRaw(path, contents)
+    } else {
+      Promise.reject(
+        JsError.throwWithMessage(
+          "No desktop runtime — filesystem access requires Gossamer or Tauri",
+        ),
+      )
+    }
+  }
+}
+
+======================================== */