feat: add project-review workflow (whole-project / single-feature review)

Adds the project-review workflow for code review independent of the git
diff. The scope is parsed from the user instruction: 全面/整个项目 ->
whole-project (score every source file), otherwise feature + target
keyword (locate the code with semantic search + graph queries).

- scoring_tools.py: score_review_func gains all_files=True to score every
  source file in the graph via store.get_all_files()
- main.py: score_review_tool gains all_files param; registers the
  project_review MCP prompt (prompts 6->7)
- prompts.py: project_review_prompt(scope, target) with whole-project and
  feature branches (fixed a precedence bug that truncated the feature text)
- skills.py + skills/project-review/: new read-only project-review skill
  with shared checklists
- .opencode/command/code-review-graph-project-review.md: slash command
- tests: test_project_review.py (prompt rendering), TestProjectReviewPrompt,
  skill count assertions 5->6, all_files wiring checks
- docs: prompts (6->7) + project-review entries across COMMANDS, CLAUDE,
  README (+localized), INDEX, architecture, LLM-OPTIMIZED-REFERENCE,
  CHANGELOG

README.ja-JP.md

@@ -255,8 +255,8 @@ code-review-graph serve            # MCPサーバーの起動
 | `list_repos_tool` | 登録済みリポジトリの一覧 |
 | `cross_repo_search_tool` | 全登録リポジトリを横断検索 |
 
-**MCPプロンプト**（6つのワークフローテンプレート）：
-`review_changes`, `architecture_map`, `debug_issue`, `onboard_developer`, `pre_merge_check`, `unified_review`
+**MCPプロンプト**（7つのワークフローテンプレート）：
+`review_changes`, `architecture_map`, `debug_issue`, `onboard_developer`, `pre_merge_check`, `unified_review`, `project_review`
 
 </details>