Add parallel search mode and index progress bar

Features:
- CCW smart_search: Add 'parallel' mode that runs hybrid + exact + ripgrep
  simultaneously with RRF (Reciprocal Rank Fusion) for result merging
- Dashboard: Add real-time progress bar for CodexLens index initialization
- MCP: Return progress metadata in init action response
- Codex-lens: Auto-detect optimal worker count for parallel indexing

Changes:
- smart-search.ts: Add parallel mode, RRF fusion, progress tracking
- codex-lens.ts: Add onProgress callback support, progress parsing
- codexlens-routes.ts: Broadcast index progress via WebSocket
- codexlens-manager.js: New index progress modal with real-time updates
- notifications.js: Add WebSocket event handler registration system
- i18n.js: Add English/Chinese translations for progress UI
- index_tree.py: Workers parameter now auto-detects CPU count (max 16)
- commands.py: CLI --workers parameter supports auto-detection

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

codex-lens/src/codexlens/cli/commands.py

@@ -77,7 +77,7 @@ def init(
         "-l",
         help="Limit indexing to specific languages (repeat or comma-separated).",
     ),
-    workers: int = typer.Option(4, "--workers", "-w", min=1, max=16, help="Parallel worker processes."),
+    workers: Optional[int] = typer.Option(None, "--workers", "-w", min=1, max=16, help="Parallel worker processes (default: auto-detect based on CPU count, max 16)."),
     force: bool = typer.Option(False, "--force", "-f", help="Force full reindex (skip incremental mode)."),
     no_embeddings: bool = typer.Option(False, "--no-embeddings", help="Skip automatic embedding generation (if semantic deps installed)."),
     embedding_model: str = typer.Option("code", "--embedding-model", help="Embedding model profile: fast, code, multilingual, balanced."),

codex-lens/src/codexlens/storage/index_tree.py

@@ -98,7 +98,7 @@ class IndexTreeBuilder:
         self,
         source_root: Path,
         languages: List[str] = None,
-        workers: int = 4,
+        workers: int = None,
         force_full: bool = False,
     ) -> BuildResult:
         """Build complete index tree for a project.
@@ -127,6 +127,11 @@ class IndexTreeBuilder:
         if not source_root.exists():
             raise ValueError(f"Source root does not exist: {source_root}")
 
+        # Auto-detect optimal worker count if not specified
+        if workers is None:
+            workers = min(os.cpu_count() or 4, 16)  # Cap at 16 workers
+            self.logger.debug("Auto-detected %d workers for parallel indexing", workers)
+
         # Override incremental mode if force_full is True
         use_incremental = self.incremental and not force_full
         if force_full:
@@ -238,7 +243,7 @@ class IndexTreeBuilder:
         self,
         source_path: Path,
         languages: List[str] = None,
-        workers: int = 4,
+        workers: int = None,
     ) -> BuildResult:
         """Incrementally update a subtree.