refactor(claude): Simplify code-review command to use reviewing-changes skill

This commit simplifies the `code-review` command by delegating the core logic to the new `reviewing-changes` skill.

The previous verbose template, which included detailed instructions and a complex output format for manual reviews, has been removed. The new implementation directly invokes the `reviewing-changes` skill with the pull request URL.

Specific changes include:
- Replaced the extensive review template in `.claude/commands/code-review.md` with a simpler command definition.
- The command now accepts a PR URL as its primary argument.
- It is explicitly defined to use the `reviewing-changes` skill for the review process.
- Output requirements are now specified to be written to `pr-review-summary.md` and `pr-review-inline-comments.md`.

.claude/commands/code-review.md

@@ -1,82 +1,19 @@
-Use this template to review a PR diff with focused, actionable feedback.
+---
+description: Initiate a code review on a specific pull request, using the `reviewing-changes` skill.
+argument-hint: PR URL
+version: 1.0.0
+---
 
 ## INPUTS
 
-- PR diff - the pull request diff to review
-- (optional) PR description
-- (optional) Ticket links
+- PR
 
 ## INSTRUCTIONS
 
-1. Scan the PR diff for correctness, style, security, and performance.
-2. Ground comments in the project context (frameworks, languages, databases, messaging systems).
-3. Prefer specific inline suggestions with minimal working patches.
-4. Flag test gaps and missing docs. Propose concrete test cases.
-5. Label severity: Blocker, Major, Minor, Nit.
-6. Keep lines ≤80 chars.
+Use the `reviewing-changes` skill to review pull request $1. This is a local code review, do not post any feedback to GitHub.
 
 ## OUTPUT FORMAT
 
-### Summary
-- **Scope:**
-- **Impact:**
-- **Risk level:**
-
-### Positives
-- **Code quality wins:**
-- **Good patterns:**
-- **Tests/documentation:**
-
-### Issues by Severity
-
-#### Blockers
-- [file:line] Problem → Why it matters → Fix suggestion
-  ```
-  // patchlet
-  ```
-
-#### Major
-- ...
-
-#### Minor
-- ...
-
-#### Nits
-- ...
-
-### Security & Compliance
-- **Authentication/authorization:**
-- **Input validation/injection prevention:**
-- **Secrets/logging/sensitive data:**
-- **Third-party integrations:**
-- **Data privacy/compliance:**
-
-### Performance
-- **Hot paths:**
-- **Database query optimization:**
-- **Caching/TTL:**
-- **Async/concurrency handling:**
-
-### Testing Gaps
-- **Unit:**
-- **Integration/e2e:**
-- **Property/fuzz:**
-- **Load/reliability:**
-
-### Documentation
-- **Changelog:**
-- **Architecture notes:**
-- **README/code comments:**
-
-### Inline Review
-- [file path]
-    - line X: comment
-    - line Y: comment
-
-### Review Checklist
-- [ ] Builds/CI green
-- [ ] Lint/format pass
-- [ ] Tests updated/added
-- [ ] Backward compatible
-- [ ] Feature flagged
-- [ ] Observability added
+- Overall summary must be written to `pr-review-summary.md`.
+- Inline comments must be written to `pr-review-inline-comments.md`.
+- Output files must be written, even if there are no issues found.