Umbrella for a set of improvements to fix in one batch (see sub-issues for the terminal work).

1. Setting: show hidden folders by default

The file manager has a per-session "Hidden" toggle that defaults to off and filters out dotfiles client-side (ui/src/components/FileBrowser.vue). Add a persisted setting in the Settings page, stored through the agent settings API like the existing options, that controls this default.

Default: enabled (hidden folders visible unless the user turns it off).

2. Optional app/template selection for image and compose deploys

Only Easy mode associates a deployment with a template (template_id). Image and compose deploys get none of the template scaffolding: deploying a Laravel app from an image means creating storage/ and all its subdirectories by hand.

Allow optionally selecting an app/template in image and compose modes. The deploy keeps the user's image or compose content but still benefits from:

• pre-created directories (Laravel storage/*, bootstrap/cache, etc.)
• default environment variables for the selected app
• default bind mounts