feat(15-03): update E2E seed and auth tests for OIDC architecture

- E2E seed creates API key instead of user for authentication
- Auth service tests cover only API key CRUD (removed user/session tests)
- Auth middleware tests validate three-way auth: API key, Bearer token, OIDC session
- Auth route tests mock getAuth for OIDC session, test /me and /keys endpoints
- Remove all references to createUser, verifyPassword, createSession in auth tests

e2e/seed.ts

@@ -202,9 +202,13 @@ export async function seedTestDatabase() {
 		])
 		.run();
 
-	// ── User ──
-	const passwordHash = await Bun.password.hash("password123");
-	db.insert(schema.users).values({ username: "admin", passwordHash }).run();
+	// ── API Key for E2E Authentication ──
+	const rawKey = "e2e-test-api-key-for-gearbox-testing";
+	const keyHash = await Bun.password.hash(rawKey);
+	const keyPrefix = rawKey.slice(0, 8);
+	db.insert(schema.apiKeys)
+		.values({ name: "E2E Test Key", keyHash, keyPrefix })
+		.run();
 
 	// ── Settings ──
 	db.insert(schema.settings)