feat: Add session memory system with pgvector

- Add session_memories table for persistent learnings
- Add memory_add, memory_search, memory_list, memory_context tools
- Supports semantic search via embeddings
- Categories: pattern, fix, preference, gotcha, architecture

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

src/tools/index.ts

@@ -546,4 +546,58 @@ export const toolDefinitions = [
       },
     },
   },
+
+  // Memory Tools
+  {
+    name: 'memory_add',
+    description: 'Store a learning/memory for future sessions. Use at session end to persist insights.',
+    inputSchema: {
+      type: 'object',
+      properties: {
+        category: { type: 'string', enum: ['pattern', 'fix', 'preference', 'gotcha', 'architecture'], description: 'Memory category' },
+        title: { type: 'string', description: 'Short title for the memory' },
+        content: { type: 'string', description: 'The learning/insight to remember' },
+        context: { type: 'string', description: 'When/where this applies (optional)' },
+        project: { type: 'string', description: 'Project this relates to (optional)' },
+      },
+      required: ['category', 'title', 'content'],
+    },
+  },
+  {
+    name: 'memory_search',
+    description: 'Search memories semantically. Returns relevant learnings for current context.',
+    inputSchema: {
+      type: 'object',
+      properties: {
+        query: { type: 'string', description: 'Search query' },
+        project: { type: 'string', description: 'Filter by project (optional)' },
+        category: { type: 'string', enum: ['pattern', 'fix', 'preference', 'gotcha', 'architecture'], description: 'Filter by category (optional)' },
+        limit: { type: 'number', description: 'Max results (default: 5)' },
+      },
+      required: ['query'],
+    },
+  },
+  {
+    name: 'memory_list',
+    description: 'List stored memories (non-semantic)',
+    inputSchema: {
+      type: 'object',
+      properties: {
+        project: { type: 'string', description: 'Filter by project (optional)' },
+        category: { type: 'string', enum: ['pattern', 'fix', 'preference', 'gotcha', 'architecture'], description: 'Filter by category (optional)' },
+        limit: { type: 'number', description: 'Max results (default: 20)' },
+      },
+    },
+  },
+  {
+    name: 'memory_context',
+    description: 'Get memories relevant to current session context. Use at session start.',
+    inputSchema: {
+      type: 'object',
+      properties: {
+        project: { type: 'string', description: 'Current project' },
+        task_description: { type: 'string', description: 'Description of planned work (for semantic matching)' },
+      },
+    },
+  },
 ];