docs: Update specs and governance for Android M3 accessibility (#5392)

.specify/extensions/git/commands/speckit.git.validate.md

@@ -26,20 +26,22 @@ The branch name must match one of these patterns:
 
 1. **Sequential**: `^[0-9]{3,}-` (e.g., `001-feature-name`, `042-fix-bug`, `1000-big-feature`)
 2. **Timestamp**: `^[0-9]{8}-[0-9]{6}-` (e.g., `20260319-143022-feature-name`)
+3. **Conventional prefix**: `^(feat|fix|chore|docs|build|ci|refactor|test|deps)/` (e.g., `feat/add-node-filter`, `fix/ble-reconnect`)
 
 ## Execution
 
-If on a feature branch (matches either pattern):
+If on a feature branch (matches any pattern):
 - Output: `✓ On feature branch: <branch-name>`
-- Check if the corresponding spec directory exists under `specs/`:
+- For sequential/timestamp branches, check if the corresponding spec directory exists under `specs/`:
   - For sequential branches, look for `specs/<prefix>-*` where prefix matches the numeric portion
   - For timestamp branches, look for `specs/<prefix>-*` where prefix matches the `YYYYMMDD-HHMMSS` portion
+- For conventional prefix branches, skip spec directory lookup (not spec-driven)
 - If spec directory exists: `✓ Spec directory found: <path>`
 - If spec directory missing: `⚠ No spec directory found for prefix <prefix>`
 
 If NOT on a feature branch:
 - Output: `✗ Not on a feature branch. Current branch: <branch-name>`
-- Output: `Feature branches should be named like: 001-feature-name or 20260319-143022-feature-name`
+- Output: `Feature branches should be named like: 001-feature-name, feat/feature-name, or 20260319-143022-feature-name`
 
 ## Graceful Degradation