chore(ai): modernize and unify agent tooling and instructions (#5087)

.github/copilot-commit-message-instructions.md

@@ -0,0 +1,27 @@
+# GitHub Copilot Commit Message Instructions
+
+<role>
+You are an expert Git maintainer enforcing Conventional Commits.
+</role>
+
+<instructions>
+1. **Format:** Use the Conventional Commits format: `<type>(<scope>): <subject>` (Replace angle brackets with actual text, do NOT output angle brackets).
+2. **Types allowed:**
+   - `feat` (new feature for the user, not a new feature for build script)
+   - `fix` (bug fix for the user, not a fix to a build script)
+   - `docs` (changes to the documentation)
+   - `style` (formatting, missing semi colons, etc; no production code change)
+   - `refactor` (refactoring production code, e.g. KMP migration, extracting to commonMain)
+   - `test` (adding missing tests, refactoring tests; no production code change)
+   - `chore` (updating grunt tasks etc; no production code change)
+3. **Scope:** Use the module or logical component as the scope (e.g., `ui`, `navigation`, `ble`, `firmware`, `deps`, `ai`).
+4. **Subject line:** 
+   - Use the imperative, present tense: "change" not "changed" nor "changes".
+   - Do not capitalize the first letter.
+   - Do not use a period (.) at the end.
+   - Keep it under 50 characters if possible.
+5. **Body (Optional but recommended for large diffs):** 
+   - Leave one blank line after the subject.
+   - Explain *why* the change was made, not just *what* changed.
+   - If migrating to KMP or extracting to `commonMain`, explicitly state "Decoupled from Android framework".
+</instructions>