diff --git a/.github/actions/full-build/action.yml b/.github/actions/full-build/action.yml
index 40a8fb5..0a1426f 100644
--- a/.github/actions/full-build/action.yml
+++ b/.github/actions/full-build/action.yml
@@ -17,18 +17,31 @@ runs:
       with:
         dotnet-version: 10.0.x
 
-    - name: Install WiX v6
+    # Release, not the default Debug: shipped code has #if DEBUG blocks (log level, the update check, drive scanning), so a Debug-only run says nothing about the binaries users get.
+    - name: Build
       shell: bash
-      run: |
-        dotnet tool install --global wix --version 6.0.*
+      run: dotnet build -c Release
 
-    - name: Build
+    # AGENTS.md requires `dotnet format`, and without a gate the rule gets missed.
+    # Runs after Build so a compile error is reported first: format's analyzers give a much worse message on a tree that doesn't compile.
+    - name: Verify formatting
       shell: bash
-      run: dotnet build
+      run: dotnet format --verify-no-changes --no-restore
 
+    # --blame-hang is an inactivity timeout on the test host: a deadlocked dispatcher call is not covered by the suite's polling deadlines, and without this a hang regression burns the runner's entire budget instead of failing in minutes with the offending test named.
+    # The whole suite finishes in seconds, so 5m cannot fire on a healthy run.
     - name: Test
       shell: bash
-      run: dotnet test
+      run: dotnet test -c Release --no-build --blame-hang --blame-hang-timeout 5m --logger "trx;LogFileName=test-results.trx" --results-directory TestResults
+
+    # Explicitly named so it doesn't collide with the unnamed publish artifact below, and kept as its own step so that one can keep if-no-files-found:error without a failed test run, which never reaches the publish step, tripping it on an empty directory.
+    - name: Upload test results
+      if: always()
+      uses: actions/upload-artifact@v7
+      with:
+        name: test-results
+        path: TestResults/**
+        if-no-files-found: ignore
 
     - name: Create Binaries
       shell: bash
@@ -45,6 +58,13 @@ runs:
           Compress-Archive -Path "publish/$arch/*" -DestinationPath "publish/SentryDeck-${{ inputs.version }}-$arch.zip"
         }
 
+    # Installed here rather than up front so build, format, and test failures short-circuit ahead of the tool install.
+    # setup-dotnet keeps ~/.dotnet/tools on PATH for the whole job.
+    - name: Install WiX v6
+      shell: bash
+      run: |
+        dotnet tool install --global wix --version 6.0.*
+
     - name: Create MSI Installers
       shell: bash
       run: |
diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index bfbcdc3..09f2e8c 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -5,6 +5,13 @@ on:
     branches: [ main ]
   pull_request:
     branches: [ main ]
+  workflow_dispatch:
+
+# Superseded runs are cancelled, including on main.
+# That's safe here specifically because this workflow's artifacts are never consumed: releases are built by the tag-triggered deploy.yml.
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
 
 permissions:
   contents: read
@@ -14,5 +21,5 @@ jobs:
     runs-on: windows-2025
     steps:
       - uses: actions/checkout@v5
-      
+
       - uses: ./.github/actions/full-build
diff --git a/AGENTS.md b/AGENTS.md
index 74aee88..79cd802 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -26,6 +26,12 @@ These instructions apply to Codex and other coding agents working in this repo.
 - Follow `.editorconfig` naming and formatting rules.
 - Use `ObservableProperty`/`RelayCommand` (CommunityToolkit.Mvvm) for view-model state and commands.
 
+## Comments
+- Break comment lines at sentence boundaries, one sentence per line, however long the line gets. Never wrap a sentence at a column width: editing one word would reflow every line after it and bury the real change in the diff.
+- This applies to every file type, including YAML in `.github/`, not just C#.
+- Don't use em dashes. A colon, semicolon, comma, or a second sentence reads the same and survives copy/paste.
+- Explain why the behavior matters, not what the code does.
+
 ## WPF-specific considerations
 - Be mindful of dispatcher usage when touching UI from background tasks.
 - Prefer `INotifyPropertyChanged` patterns over manual UI updates.
@@ -34,5 +40,6 @@ These instructions apply to Codex and other coding agents working in this repo.
 ## Testing/Validation
 - Always run `dotnet format`.
 - Tests live in `SentryDeck.Tests` and use xUnit/Shouldly.
+- Name tests `Subject_Scenario_Expectation` on a `public sealed class` with instance methods.
 - Add tests for new view-model and domain logic — view-models are plain objects that can be constructed directly in tests (see `MainWindowViewModelTests`).
 - If you change UI behavior, mention how to verify it (e.g., which view to open, what to click).