Build a photo frame web app intended to run well on Val Town using a no-build Deno/Hono architecture.

The app should:

• Let users pick multiple photos from their device
• Show a simple setup screen with thumbnails
• Allow removing photos before playback
• Allow adding captions to photos
• Start a fullscreen-style slideshow without depending on the Fullscreen API
• Auto-advance through photos with configurable timing
• Support manual next/previous navigation
• Show captions while photos are presented
• Auto-hide presentation controls when the mouse is idle
• Persist collection metadata and slideshow settings

• Deno runtime
• Hono HTTP app
• Hono JSX renders the HTML shell
• Hono serves the client JavaScript and CSS files

• Plain browser JavaScript in static/app.js
• Direct DOM rendering for setup and player modes
• No Preact runtime
• No Vite build step

• IndexedDB stores image blobs and local collection metadata for reliable browser-side persistence
• localStorage stores lightweight UI preferences only
• A remote storage adapter will later support Val Town blob storage for cross-device persistence

• id
• name
• createdAt
• updatedAt
• settings
• photoIds

• id
• name
• caption
• width
• height
• size
• createdAt
• file

• intervalSeconds
• fitMode
• shuffle
• loop
• crossfade

• Hono app shell
• Plain client-side JavaScript
• Photo upload
• Thumbnail preview list
• Caption editing
• Remove photo
• Play mode
• Auto-advance
• Manual controls
• Caption overlay
• Crossfade transition option
• Auto-hiding player controls
• Local persistence in browser

• Val Town blob upload adapter
• Collection metadata sync
• Resume saved collections across devices

• Image compression on upload
• Multiple collections
• Shareable saved frame URLs