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/storage/sqlite_store.py

@@ -0,0 +1,97 @@
+"""
+SQLite storage backend for short-term memory.
+
+Provides initialization and connection management for SQLite database.
+"""
+import sqlite3
+from pathlib import Path
+from core.config import SHORT_TERM_DB
+from core.logger import setup_logger
+
+logger = setup_logger('sqlite_store', service_name='memory_service')
+
+
+class SQLiteStore:
+    """SQLite storage backend for short-term memory"""
+
+    def __init__(self, db_path: str = None):
+        """
+        Initialize SQLite store.
+
+        Args:
+            db_path: Path to SQLite database file (defaults to SHORT_TERM_DB config)
+        """
+        self.db_path = db_path or str(SHORT_TERM_DB)
+        self.conn = None
+
+    def connect(self) -> sqlite3.Connection:
+        """
+        Connect to SQLite database and initialize schema.
+
+        Returns:
+            SQLite connection object
+        """
+        self.conn = sqlite3.connect(self.db_path)
+        self._init_schema()
+        logger.info(f"[μ] SQLite connected: {self.db_path}")
+        return self.conn
+
+    def _init_schema(self):
+        """Initialize simplified short-term SQLite database schema"""
+        cursor = self.conn.cursor()
+
+        # Simplified short-term memory table (no embeddings, fast queries)
+        cursor.execute("""
+        CREATE TABLE IF NOT EXISTS short_term_memory (
+            id TEXT PRIMARY KEY,
+            timestamp DATETIME DEFAULT CURRENT_TIMESTAMP,
+            content TEXT NOT NULL,
+            identities TEXT,
+            interaction_id TEXT,
+            modality TEXT DEFAULT 'dialogue',
+            metadata TEXT
+        )
+        """)
+
+        # Index for fast chronological queries
+        cursor.execute("""
+        CREATE INDEX IF NOT EXISTS idx_timestamp
+        ON short_term_memory(timestamp DESC)
+        """)
+
+        # Identities table (still useful for all layers)
+        cursor.execute("""
+        CREATE TABLE IF NOT EXISTS identities (
+            id TEXT PRIMARY KEY,
+            display_name TEXT,
+            role TEXT,
+            intimacy REAL DEFAULT 0.0,
+            last_seen DATETIME,
+            last_spoken DATETIME,
+            metadata TEXT
+        )
+        """)
+
+        self.conn.commit()
+        logger.info("[μ] SQLite schema initialized")
+
+    def get_connection(self) -> sqlite3.Connection:
+        """
+        Get the active database connection.
+
+        Returns:
+            SQLite connection object
+
+        Raises:
+            RuntimeError: If connection has not been established
+        """
+        if self.conn is None:
+            raise RuntimeError("SQLite connection not established. Call connect() first.")
+        return self.conn
+
+    def close(self):
+        """Close the database connection"""
+        if self.conn:
+            self.conn.close()
+            self.conn = None
+            logger.info("[μ] SQLite connection closed")