feat: add knowledge management functionality with CRUD operations and database schema

- Implemented KnowledgeHandler for managing knowledge groups and items, including listing, creating, updating, and deleting operations.
- Added database migration scripts to create necessary tables for knowledge management, including knowledge_groups, knowledge_items, knowledge_parse_tasks, and knowledge_chunks_meta.
- Introduced prompt_rule_knowledge_groups table to associate prompt rules with knowledge groups.

server/internal/shared/config/config_test.go

@@ -44,6 +44,51 @@ llm:
 	}
 }
 
+func TestLoadPrefersEnvRetrievalAndQdrantSettings(t *testing.T) {
+	t.Setenv("SILICONFLOW_API_KEY", "siliconflow-env-key")
+	t.Setenv("SILICONFLOW_EMBEDDING_MODEL", "env-embedding")
+	t.Setenv("SILICONFLOW_RERANKER_MODEL", "env-reranker")
+	t.Setenv("QDRANT_API_KEY", "qdrant-env-key")
+	t.Setenv("QDRANT_URL", "qdrant-env:6334")
+	t.Setenv("QDRANT_COLLECTION", "env_collection")
+
+	configPath := writeTestConfig(t, `
+qdrant:
+  url: qdrant-config:6334
+  api_key: "qdrant-config-key"
+  collection: "config_collection"
+retrieval:
+  provider: siliconflow
+  api_key: "retrieval-config-key"
+  embedding_model: "config-embedding"
+  reranker_model: "config-reranker"
+`)
+
+	cfg, err := Load(configPath)
+	if err != nil {
+		t.Fatalf("Load() error = %v", err)
+	}
+
+	if cfg.Retrieval.APIKey != "siliconflow-env-key" {
+		t.Fatalf("expected env retrieval api key, got %q", cfg.Retrieval.APIKey)
+	}
+	if cfg.Retrieval.EmbeddingModel != "env-embedding" {
+		t.Fatalf("expected env embedding model, got %q", cfg.Retrieval.EmbeddingModel)
+	}
+	if cfg.Retrieval.RerankerModel != "env-reranker" {
+		t.Fatalf("expected env reranker model, got %q", cfg.Retrieval.RerankerModel)
+	}
+	if cfg.Qdrant.APIKey != "qdrant-env-key" {
+		t.Fatalf("expected env qdrant api key, got %q", cfg.Qdrant.APIKey)
+	}
+	if cfg.Qdrant.URL != "qdrant-env:6334" {
+		t.Fatalf("expected env qdrant url, got %q", cfg.Qdrant.URL)
+	}
+	if cfg.Qdrant.Collection != "env_collection" {
+		t.Fatalf("expected env qdrant collection, got %q", cfg.Qdrant.Collection)
+	}
+}
+
 func writeTestConfig(t *testing.T, body string) string {
 	t.Helper()