feat(codexlens): add staged settings for advanced configuration and update related components

- Added new staged settings in config.py for coarse_k, lsp_depth, stage2_mode, and clustering strategy.
- Updated config-handlers.ts to handle new staged settings and map environment variables.
- Enhanced codexlens.json localization files for English and Chinese to include new staged settings.
- Modified astgrep_js_ts_processor.py to improve import handling for named imports.
- Updated JavaScript and TypeScript patterns to support new import formats.
- Added tests for staged settings loading and performance benchmarks for stage-2 expansion.

ccw/frontend/src/locales/en/codexlens.json

@@ -310,6 +310,10 @@
     "searchStrategy": "Search Strategy",
     "coarseK": "Coarse K",
     "fineK": "Fine K",
+    "stagedStage2Mode": "Stage-2 Mode",
+    "stagedClusteringStrategy": "Clustering Strategy",
+    "stagedClusteringMinSize": "Cluster Min Size",
+    "enableStagedRerank": "Enable Rerank",
     "useAstGrep": "Use ast-grep",
     "staticGraphEnabled": "Static Graph",
     "staticGraphRelationshipTypes": "Relationship Types",

ccw/frontend/src/locales/zh/codexlens.json

@@ -310,6 +310,10 @@
     "searchStrategy": "搜索策略",
     "coarseK": "粗筛 K 值",
     "fineK": "精筛 K 值",
+    "stagedStage2Mode": "Stage-2 模式",
+    "stagedClusteringStrategy": "聚类策略",
+    "stagedClusteringMinSize": "最小聚类大小",
+    "enableStagedRerank": "启用重排序",
     "useAstGrep": "使用 ast-grep",
     "staticGraphEnabled": "启用静态图",
     "staticGraphRelationshipTypes": "关系类型",