[codex] add custom rclone destinations

[kitwongpixel]

What changed

• Added a Custom Rclone Remote destination provider so Dokploy can target non-S3 rclone remotes for backups and restores.
• Kept the existing S3 path intact for current destinations.
• Updated the destination dialog and test-connection flow to validate and present custom remote inputs.
• Refactored backup/restore path building to use a generic rclone root helper instead of hard-coding :s3:.
• Added regression coverage for rclone path construction and custom destination flags.

Why

Issue #416 asks for backup support to more destination types. The previous implementation was effectively S3-only because backup and restore paths were always built from :s3:. This change makes the destination layer generic enough to handle other rclone remotes without a schema migration.

Validation

• pnpm exec biome check apps/dokploy/components/dashboard/settings/destination/handle-destinations.tsx apps/dokploy/server/api/routers/destination.ts apps/dokploy/__test__/utils/backups.test.ts packages/server/src/db/schema/destination.ts packages/server/src/utils/backups/utils.ts
• pnpm -C apps/dokploy exec vitest --config __test__/vitest.config.ts --run __test__/utils/backups.test.ts

Notes

• I also ran a broader typecheck attempt, but the full workspace typecheck was too large for a quick pass in this environment. The focused helper test passes, and the edited files are Biome-clean.