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/tenant/transport/router.go

@@ -83,6 +83,18 @@ func RegisterRoutes(app *bootstrap.App) {
 	brands.PUT("/:id/competitors/:cid", brandHandler.UpdateCompetitor)
 	brands.DELETE("/:id/competitors/:cid", brandHandler.DeleteCompetitor)
 
+	knowledge := protected.Group("/tenant/knowledge")
+	knowledgeHandler := NewKnowledgeHandler(app)
+	knowledge.GET("/groups", knowledgeHandler.ListGroups)
+	knowledge.POST("/groups", knowledgeHandler.CreateGroup)
+	knowledge.PUT("/groups/:gid", knowledgeHandler.UpdateGroup)
+	knowledge.DELETE("/groups/:gid", knowledgeHandler.DeleteGroup)
+	knowledge.GET("/items", knowledgeHandler.ListItems)
+	knowledge.POST("/items/text", knowledgeHandler.CreateTextItem)
+	knowledge.POST("/items/url", knowledgeHandler.CreateURLItem)
+	knowledge.POST("/items/file", knowledgeHandler.CreateFileItem)
+	knowledge.DELETE("/items/:id", knowledgeHandler.DeleteItem)
+
 	// Prompt Rules
 	promptRules := protected.Group("/tenant/prompt-rules")
 	prHandler := NewPromptRuleHandler(app)