Merge NM-App-405-fix-gitignore-add-claude-web-claire into dev

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.gitignore

@@ -54,4 +54,7 @@ app.*.map.json
 
 # Generated Drift/Riverpod files — keep .g.dart in VCS so CI doesn't need codegen
 # (do NOT add *.g.dart here)
-.claude/worktrees/
+# AITM / build artifacts
+.claude/
+.claire/
+web/

DocumentSW/gitignore-aitm-artifacts.md

@@ -0,0 +1,21 @@
+# .gitignore — AITM/Build Artifact Exclusions
+
+## What was done
+Extended `.gitignore` to exclude three directories that should never be committed:
+
+| Pattern | Purpose |
+|---------|---------|
+| `.claude/` | AITM internal database and worktree files |
+| `.claire/` | AITM worktree metadata files |
+| `web/` | Flutter web build output |
+
+## Files changed
+- `.gitignore` — replaced narrow `.claude/worktrees/` entry with broader `.claude/`, and added `.claire/` and `web/`
+
+## Key details
+The previous entry `.claude/worktrees/` only excluded the worktrees subdirectory. The replacement `.claude/` covers the entire AITM internal directory (including the database and any future subdirectories).
+
+All three patterns were added under a shared `# AITM / build artifacts` comment block.
+
+## Tests
+`test/gitignore_test.dart` — 3 tests verifying each of the three entries is present in `.gitignore`.