Chore: Update with-supabase example to Next.js 16

[dijonmusters]

What?

Upgrade with-supabase example to be compatible with Next.js 16

Why?

1. Users get console warnings about middleware vs proxy
2. Enabling Cache Components config results in build errors for async behaviour outside Suspense boundary
3. Turbopack flag is default and therefore, no longer necessary on npm run dev

How?

1. Renamed all instances of middleware to proxy
2. Wraped async behaviour in Suspense boundaries
3. Removed --turbopack flag from npm run dev

[ijjk]

Allow CI Workflow Run

• approve CI run for commit: 8063812

Note: this should only be enabled once the PR is ready to go and can only be enabled by a maintainer

[ijjk]

Allow CI Workflow Run

• approve CI run for commit: e57ea68

Note: this should only be enabled once the PR is ready to go and can only be enabled by a maintainer