fix(cloudflare-workers): add database override for Drizzle on CF Workers

[melihakyol06]

Description

db: db({ schema, migrations }) from rivetkit/db/drizzle fails on Cloudflare Workers with:

SqliteVfs instance not provided in context. The driver must provide a sqliteVfs instance.

Root cause: The @rivetkit/cloudflare-workers driver does not implement overrideRawDatabaseClient or overrideDrizzleDatabaseClient. The Drizzle db() provider only supports the KV-backed SQLite VFS path, which relies on a dynamic import of @rivetkit/sqlite-vfs that wrangler cannot resolve at build time. Durable Objects already have native SQLite via ctx.storage.sql, but the driver never exposes it to the db provider.

Type of change

• Bug fix (non-breaking change which fixes an issue)

Changes

@rivetkit/cloudflare-workers — actor-driver.ts

• overrideRawDatabaseClient(actorId) — wraps DO native storage.sql as a RawDatabaseClient
• overrideDrizzleDatabaseClient(actorId) — returns DO DurableObjectStorage for Drizzle

rivetkit — db/drizzle/mod.ts

• createClient checks ctx.overrideDrizzleDatabaseClient before VFS fallback, creates drizzle-orm/durable-sqlite instance
• Added runDOInlineMigrations for DO SQLite migrations

How Has This Been Tested?

Tested with a standalone CF Workers project using wrangler dev and wrangler deploy:

• Drizzle queries (insert, select with .returning()) work via c.db
• c.state alongside c.db — both persist correctly
• Migrations run correctly — __drizzle_migrations table populated in CF dashboard
• pnpm check-types passes for both rivetkit and @rivetkit/cloudflare-workers
• Existing tests unaffected

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• My changes generate no new warnings
• New and existing unit tests pass locally with my changes