Docs: Create documentation for the Greenshot plugin

docs/plugins/README.md

@@ -90,6 +90,7 @@ Deep-merges TOML settings into `%USERPROFILE%\.rustup\settings.toml`.
 | `autohotkey` | Manages an AutoHotkey v2 bootstrap script and WinHome-owned settings block. | `config_provider` | [Details](#autohotkey) |
 | `espanso`    | Manages Espanso text expansion rules in `base.yml`.                         | `config_provider` | [Details](#espanso)    |
 | `everything` | Manages Everything search application configuration.                        | `config_provider` | [Details](#everything) |
+| `greenshot`  | Manages Greenshot screenshot utility settings in `Greenshot.ini`.           | `config_provider` | [Details](./greenshot.md) |
 | `keepassxc`  | Manages KeePassXC INI settings.                                             | `config_provider` | [Details](#keepassxc)  |
 | `powertoys`  | Manages PowerToys general settings and supported module settings.           | `config_provider` | [Details](#powertoys)  |
 | `sharex`     | Manages ShareX `ShareX.json`.                                               | `config_provider` | [Details](#sharex)     |

docs/plugins/greenshot.md

@@ -0,0 +1,97 @@
+# Greenshot Plugin
+
+## Overview
+
+The Greenshot plugin manages the configuration of the Greenshot screenshot utility by deep-merging settings into `%APPDATA%\Greenshot\Greenshot.ini`.
+
+## Prerequisites
+
+- Windows operating system with `%APPDATA%` available
+- Greenshot installed (or a writable `%APPDATA%\Greenshot` directory)
+
+## Configuration Schema
+
+The plugin accepts a top-level YAML object with a single configuration field:
+
+| Field | Type | Default | Description |
+| ----- | ---- | ------- | ----------- |
+| `settings` | object | none | Key-value pairs to write to `Greenshot.ini`. |
+
+### Key Mapping Format
+
+Because Greenshot's configuration uses the INI format with multiple sections, keys in `settings` must map to their respective sections in `Greenshot.ini` using a backslash (`\`) as a separator:
+
+- **Section Keys**: Format the key as `"Section\\Key"` (or `'Section\Key'` in single quotes) to target a specific section.
+- **Default Section**: If no backslash is present in the key, it defaults to the `[General]` section.
+
+### Common Configuration Sections and Keys
+
+While any settings accepted by Greenshot can be written, here are some commonly used sections and keys:
+
+| Compound Key | Type | Description |
+| ------------ | ---- | ----------- |
+| `General\Language` | string | Interface language code (e.g., `"en-US"`). |
+| `Capture\CaptureMousepointer` | boolean | If `true`, the cursor is included in screenshots. |
+| `Capture\CaptureMode` | string | The capture mode (e.g., `"Region"`, `"Window"`). |
+| `Destination\CopyToClipboard` | boolean | If `true`, screenshots are automatically copied to the clipboard. |
+| `Core\OutputFilePath` | string | The directory path where screenshots are saved. |
+| `Core\OutputFormat` | string | Screenshot file format (e.g., `"png"`, `"jpg"`, `"gif"`). |
+
+## Usage Examples
+
+### Configure file output options
+
+Save screenshots directly to a custom path in PNG format:
+
+```yaml
+extensions:
+  greenshot:
+    settings:
+      "Core\\OutputFilePath": "C:\\Users\\Username\\Pictures\\Screenshots"
+      "Core\\OutputFormat": "png"
+```
+
+### Enable clipboard destination and capture cursor
+
+Include the mouse cursor and automatically copy captured screenshots to the clipboard:
+
+```yaml
+extensions:
+  greenshot:
+    settings:
+      "Capture\\CaptureMousepointer": true
+      "Destination\\CopyToClipboard": true
+```
+
+### Combined capture and interface configuration
+
+Configure the display language, capture options, and output settings in one block:
+
+```yaml
+extensions:
+  greenshot:
+    settings:
+      "General\\Language": "en-US"
+      "Capture\\CaptureMousepointer": false
+      "Destination\\CopyToClipboard": true
+      "Core\\OutputFilePath": "D:\\Screenshots"
+      "Core\\OutputFormat": "png"
+```
+
+## Verification Steps
+
+1. Apply your WinHome configuration.
+2. Verify that `%APPDATA%\Greenshot\Greenshot.ini` has been updated with the specified sections and values. You can run:
+   ```powershell
+   Get-Content "$env:APPDATA\Greenshot\Greenshot.ini"
+   ```
+3. Open the Greenshot settings panel from the system tray and confirm the changes are reflected.
+
+## Notes / Caveats
+
+- This plugin is Windows-specific as it targets the AppData directory structure.
+- Values are written as strings (`"True"`/`"False"` for booleans, and standard string representation for others).
+- Existing configurations in `Greenshot.ini` are preserved unless explicitly overwritten by the settings provided.
+- The configuration file is updated atomically via a temporary file write followed by a replace operation to prevent corruption.
+- If Greenshot is currently running, it is recommended to close the application before applying settings, or restart it afterward for the changes to take effect.
+- Supports `dryRun` mode to check for changes without modifying the filesystem.