Add SeaweedFS install app

[CarlosZiegler]

Summary

Adds SeaweedFS as a standalone Install App option for self-hosted S3-compatible object storage.

This gives users another open-source storage choice alongside MinIO.

Changes

• Add a seaweedfs catalog template using chrislusf/seaweedfs
• Configure the SeaweedFS S3 gateway with generated access credentials
• Persist SeaweedFS data in a named volume
• Expose both the Filer UI and S3 API routes
• Publish connection outputs for endpoint, access key, secret key, bucket, and region
• Mark SeaweedFS as an S3 storage source candidate for the object-storage bind flow
• Add a SeaweedFS logo mapping
• Regenerate the merged app catalog

Closes #401.

Verification

• bun packages/core/scripts/gen-catalog.ts
• bun --filter @repo/core test -- src/apps/catalog.test.ts
• bun --filter @repo/core lint
• bun --filter @repo/api lint
• git diff --check
• cd apps/dashboard && bun x tsc --noEmit

Note: full root bun run lint currently fails in the existing @repo/email package because it calls a missing nested lint script. The touched packages above pass their targeted checks.