Simplify SQLite setup instructions in AGENTS.md

Removed redundant information about SQLite database configuration and environment variables.

AGENTS.md

@@ -116,7 +116,7 @@ Whenever you modify the `prisma/schema.prisma` file, you **must** generate a cor
 
 Instead, follow this workflow:
 
-1. Ensure you have a local SQLite database configured (e.g., via `.env` setting `DATABASE_URL="file:./dev.db"`).
+1. Ensure you have a local SQLite database configured.
 2. Run the migration command:
    ```bash
    bun x prisma migrate dev --name <migration_name>
@@ -144,11 +144,6 @@ Instead, follow this workflow:
   - Exception: File names generated by `FileService` may still use `ulid()` internally, but this is separate from the database ID.
 - **Sorting**: All list APIs must order results by `id` descending (`orderBy: { id: 'desc' }`) to ensure consistent, time-based sorting (since ULIDs are sortable). Do not sort by `createdAt` as it is not indexed.
 
-## Environment Variables
-
-- `.env`: Development environment variables (`DATABASE_URL="file:./dev.db"`, `API_KEY="..."`).
-- `.env.test`: Test environment variables (`DATABASE_URL="file:./test.db"`).
-
 ## Known Issues
 
 - `bun test` module mocking can be sticky across test files running in the same process/worker. Use the dynamic import workaround in Service tests.