chore: upgrade PostgreSQL 17 and Supabase CLI 2.54.11 (#300)

## Summary

This PR upgrades the pgflow project to PostgreSQL 17 and Supabase CLI 2.54.11, removing strict version pins for Docker images and the PGMQ extension to use the latest compatible versions.

## Changes

### PostgreSQL Version Upgrade

- **PostgreSQL 15 → PostgreSQL 17** across all environments:
    - Atlas migration Docker image (`pkgs/core/atlas/Dockerfile`)
    - Edge worker test database (`pkgs/edge-worker/tests/db/compose.yaml`)
    - Supabase config files (all `config.toml` files)
    - Atlas configuration (`pkgs/core/atlas/atlas.hcl`)
    - Build and deployment scripts

### PGMQ Version Management

- Updated Atlas Docker image to use PGMQ v1.5.1 (from v1.4.4)
- Removed strict version pins to allow using latest compatible PGMQ versions in production environments
- This prepares for the next PR which requires PGMQ 1.5.0+ features

### Configuration Updates

Updated PostgreSQL version references in:

- `examples/playground/supabase/config.toml`
- `pkgs/client/supabase/config.toml`
- `pkgs/core/supabase/config.toml`
- `pkgs/edge-worker/supabase/config.toml`
- `pkgs/core/atlas/atlas.hcl`

### Database Types

- Regenerated TypeScript database types (`pkgs/core/src/database-types.ts`) to reflect PostgreSQL 17 schema
- Updated package dependencies in `pnpm-lock.yaml`

### Cleanup

- Removed temporary Supabase version tracking files:
    - `pkgs/core/supabase/.temp/pgmeta-version`
    - `pkgs/core/supabase/.temp/postgres-version`

### Documentation

- Added documentation update task to `pkgs/website/src/content/docs/deploy/update-pgflow.mdx` for upgrade procedures

## Testing

All existing tests pass with PostgreSQL 17. No functional changes to pgflow behavior.

## Impact

- **Users:** No breaking changes. Existing deployments will continue to work.
- **New Deployments:** Will use PostgreSQL 17 by default
- **Self-hosted:** Upgrading PostgreSQL version may require database migration depending on your hosting setup

## Related

- Prepares infrastructure for PR #301 which requires PGMQ 1.5.0+ features
- Part of keeping pgflow aligned with latest Supabase platform versions

Author: jumski

.changeset/upgrade-postgres-seventeen-supabase.md

@@ -0,0 +1,8 @@
+---
+'@pgflow/core': minor
+'@pgflow/client': minor
+'@pgflow/edge-worker': minor
+'@pgflow/website': minor
+---
+
+Upgrade PostgreSQL 17 and Supabase CLI 2.54.11. Removes strict version pins for Docker images and PGMQ extension to use latest compatible versions.