chore: mark review todos as complete

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

todos/005-complete-p2-warn-invalid-settings-json.md

@@ -0,0 +1,23 @@
+---
+status: pending
+priority: p2
+issue_id: "005"
+tags: [code-review, error-handling]
+dependencies: ["004"]
+---
+
+# Warn when existing settings.json is invalid JSON
+
+## Problem Statement
+When an existing `settings.json` cannot be parsed, the error is silently swallowed and the file is overwritten. Users get no warning that their settings were discarded.
+
+## Findings
+- `src/targets/gemini.ts` lines 37-41: empty catch block
+
+## Proposed Solution
+Add a `console.warn` in the catch block to inform the user that their existing settings.json could not be parsed and will be replaced.
+
+## Acceptance Criteria
+- [ ] `console.warn` emitted when settings.json parse fails
+- [ ] File is still replaced (behavior unchanged)
+- [ ] All tests pass