feat: add users, sessions, and api_keys tables

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

tests/helpers/db.ts

@@ -90,6 +90,33 @@ export function createTestDb() {
     )
   `);
 
+	sqlite.run(`
+    CREATE TABLE users (
+      id INTEGER PRIMARY KEY AUTOINCREMENT,
+      username TEXT NOT NULL UNIQUE,
+      password_hash TEXT NOT NULL,
+      created_at INTEGER NOT NULL DEFAULT (unixepoch())
+    )
+  `);
+
+	sqlite.run(`
+    CREATE TABLE sessions (
+      id TEXT PRIMARY KEY,
+      user_id INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+      expires_at INTEGER NOT NULL
+    )
+  `);
+
+	sqlite.run(`
+    CREATE TABLE api_keys (
+      id INTEGER PRIMARY KEY AUTOINCREMENT,
+      name TEXT NOT NULL,
+      key_hash TEXT NOT NULL,
+      key_prefix TEXT NOT NULL,
+      created_at INTEGER NOT NULL DEFAULT (unixepoch())
+    )
+  `);
+
 	const db = drizzle(sqlite, { schema });
 
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