feat: add APIEmbedder for remote embedding with multi-endpoint support

- Introduced APIEmbedder class to handle embeddings via a remote HTTP API.
- Implemented token packing to optimize batch sizes based on token limits.
- Added support for multiple API endpoints with round-robin dispatching.
- Included retry logic for API calls with exponential backoff on failures.
- Enhanced indexing pipeline with file exclusion checks and smart chunking strategies.
- Updated tests to cover new APIEmbedder functionality and ensure robustness.

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

@@ -290,41 +290,31 @@
   "envGroup": {
     "embedding": "Embedding",
     "reranker": "Reranker",
-    "concurrency": "Concurrency",
-    "cascade": "Cascade Search",
-    "indexing": "Indexing",
-    "chunking": "Chunking"
+    "search": "Search Pipeline",
+    "indexing": "Indexing"
   },
   "envField": {
     "backend": "Backend",
     "model": "Model",
-    "autoEmbedMissing": "Auto Build Missing Vectors",
-    "useGpu": "Use GPU",
-    "highAvailability": "High Availability",
-    "loadBalanceStrategy": "Load Balance Strategy",
-    "rateLimitCooldown": "Rate Limit Cooldown",
-    "enabled": "Enabled",
+    "localModel": "Local Model",
+    "apiUrl": "API URL",
+    "apiKey": "API Key",
+    "multiEndpoints": "Multi-Endpoint",
+    "embedDim": "Embed Dimension",
+    "apiConcurrency": "Concurrency",
+    "maxTokensPerBatch": "Max Tokens/Batch",
+    "useGpu": "Device",
     "topKResults": "Top K Results",
-    "maxWorkers": "Max Workers",
     "batchSize": "Batch Size",
-    "dynamicBatchSize": "Dynamic Batch Size",
-    "batchSizeUtilization": "Utilization Factor",
-    "batchSizeMax": "Max Batch Size",
-    "charsPerToken": "Chars Per Token",
-    "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",
-    "stripComments": "Strip Comments",
-    "stripDocstrings": "Strip Docstrings",
-    "testFilePenalty": "Test File Penalty",
-    "docstringWeight": "Docstring Weight"
+    "binaryTopK": "Binary Top K",
+    "annTopK": "ANN Top K",
+    "ftsTopK": "FTS Top K",
+    "fusionK": "Fusion K",
+    "codeAwareChunking": "Code-Aware Chunking",
+    "indexWorkers": "Index Workers",
+    "maxFileSize": "Max File Size (bytes)",
+    "hnswEf": "HNSW ef",
+    "hnswM": "HNSW M"
   },
   "install": {
     "title": "Install CodexLens",

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

@@ -290,41 +290,31 @@
   "envGroup": {
     "embedding": "嵌入模型",
     "reranker": "重排序",
-    "concurrency": "并发",
-    "cascade": "级联搜索",
-    "indexing": "索引与解析",
-    "chunking": "分块"
+    "search": "搜索流水线",
+    "indexing": "索引"
   },
   "envField": {
     "backend": "后端",
     "model": "模型",
-    "autoEmbedMissing": "缺失向量时自动构建",
-    "useGpu": "使用 GPU",
-    "highAvailability": "高可用",
-    "loadBalanceStrategy": "负载均衡策略",
-    "rateLimitCooldown": "限流冷却时间",
-    "enabled": "启用",
+    "localModel": "本地模型",
+    "apiUrl": "API 地址",
+    "apiKey": "API 密钥",
+    "multiEndpoints": "多端点",
+    "embedDim": "向量维度",
+    "apiConcurrency": "并发数",
+    "maxTokensPerBatch": "每批最大Token数",
+    "useGpu": "设备",
     "topKResults": "Top K 结果数",
-    "maxWorkers": "最大工作线程",
     "batchSize": "批次大小",
-    "dynamicBatchSize": "动态批次大小",
-    "batchSizeUtilization": "利用率因子",
-    "batchSizeMax": "最大批次大小",
-    "charsPerToken": "每 Token 字符数",
-    "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",
-    "stripComments": "去除注释",
-    "stripDocstrings": "去除文档字符串",
-    "testFilePenalty": "测试文件惩罚",
-    "docstringWeight": "文档字符串权重"
+    "binaryTopK": "二值粗筛 K",
+    "annTopK": "ANN 精筛 K",
+    "ftsTopK": "全文搜索 K",
+    "fusionK": "融合 K",
+    "codeAwareChunking": "代码感知分块",
+    "indexWorkers": "索引线程数",
+    "maxFileSize": "最大文件大小(字节)",
+    "hnswEf": "HNSW ef",
+    "hnswM": "HNSW M"
   },
   "install": {
     "title": "安装 CodexLens",