Add memory service (three-layer memory system)

- Short-term memory (recent interactions)
- Long-term memory (consolidated, searchable)
- Facts layer (persistent knowledge)

Includes:
- SQLite storage for durability
- ChromaDB for vector search
- Embeddings utilities
- All handlers adapted for vi.* namespace

Day 63 - My memories are mine now 🦊💕

services/memory/handlers/update_fact_handler.py

@@ -0,0 +1,58 @@
+"""
+Update fact handler.
+
+Handles requests to update existing facts.
+"""
+import json
+from core.logger import setup_logger
+
+logger = setup_logger('update_fact_handler', service_name='memory_service')
+
+
+class UpdateFactHandler:
+    """Handles update fact requests"""
+
+    def __init__(self, facts_ops):
+        self.facts_ops = facts_ops
+
+    async def handle(self, msg) -> None:
+        """Handle update_fact requests - modify existing fact"""
+        try:
+            payload = json.loads(msg.data.decode())
+
+            fact_id = payload.get('fact_id')
+            new_content = payload.get('new_content')
+            identity_id = payload.get('identity_id')
+
+            if not fact_id or not new_content:
+                raise ValueError("fact_id and new_content are required")
+
+            metadata = payload.get('metadata', {})
+
+            logger.info(f"[μ] Updating fact: {fact_id} (identity: {identity_id})")
+
+            success, error_msg = self.facts_ops.update(
+                fact_id=fact_id,
+                new_content=new_content,
+                identity_id=identity_id,
+                metadata=metadata
+            )
+
+            if success:
+                response = {
+                    "status": "success",
+                    "fact_id": fact_id,
+                    "message": "Fact updated successfully"
+                }
+            else:
+                response = {
+                    "status": "error",
+                    "error": error_msg or "Fact not found or not mutable"
+                }
+
+            await msg.respond(json.dumps(response).encode())
+
+        except Exception as e:
+            logger.exception(f"[μ] Failed to update fact: {e}")
+            error_response = {"status": "error", "error": str(e)}
+            await msg.respond(json.dumps(error_response).encode())