feat: add Photos group app

2026-08-25T09:46:17Z

A new group application (docs/apps.md's plug-in mechanism), following the plan in docs/photos.md. Unlike Videos/Music: several photo roots per group instead of one (photo_roots is a set, one signed op replaces it whole), a single album-grid view with no third-party matching step, and per-photo info read from the file's own EXIF at index time — no metadata service, no credential, no outbound network call at all. Protocol (meshbay-common, MNP 0.10 -> 0.11, additive): `taken_at`/`camera` on IndexEntry; `photo_roots`/`photo_roots_ack`; `OP_PHOTO_ROOTS`. Node: roster.py stores photo_roots as a group_settings entry (JSON list, same shape as enabled_apps); ops.py/webrtc_server.py validate and sign the whole set in one op, same pattern as apps_enabled; a new PhotoEnricher (indexer/enrich_photo.py) runs Pillow in its own small bounded pool, separate from the video/audio pools, producing a resized thumbnail plus the two EXIF fields — never GPS, checked by a grep-based regression test. Client: photos-app.js — one album card per directory containing images, a per-album photo grid, and a lightbox with next/previous (keyboard and buttons), zoom in/out/fit/100% starting from the actual on-screen fit percentage, and a "zip this album" button reusing files-app.js's own zip mechanism (lifted into file-utils.js's downloadDirectory so both call the same implementation). group-settings.js gets an add/remove multi-root picker, distinct from Videos/Music's single-value one. Bugs found and fixed before this ever shipped, worth keeping the story of: - enrich_photo.py read width/height from the raw image *before* applying EXIF orientation correction, and read DateTimeOriginal off the plain 0th-IFD Exif object — a real camera stores it in the Exif sub-IFD, which Pillow only exposes via get_ifd(Exif). A flat, hand-built EXIF dict round-trips through Pillow either way, which is exactly what would have hidden both bugs; the regression test builds EXIF with piexif instead, matching what real hardware produces. - photos-app.js's album grouping stripped a trailing path segment from entry.path under the assumption it still carried a filename — it doesn't (files-app.js's own convention: e.path is already the containing directory), so every album collapsed one level into its parent. Found live against a real multi-folder library. - transport.js's ADMIN_OP_TYPES allowlist (already the fix for an identical bug on video_root/apps_enabled, see 4783d81) was missing photo_roots: its admin_challenge matched no pending request and was silently dropped, so saving a photo root just timed out after 30s with no error. - daemon.py pruned a thumbnail when its file left the index (root removed or reconfigured) but never forgot the content hash was "already attempted" — the same bytes reappearing under a renamed/relocated root (an operator's real workflow) were then permanently skipped, forever, with nothing to indicate why. Discarding the attempt alongside the cache entry on prune is what makes pruning actually reversible. - packages/meshbay-client's app:// protocol handler served every file with no Cache-Control header, so Chromium was free to serve a stale cached copy indefinitely — none of several `npm run sync-ui` + reload cycles during development actually picked up the new code until the renderer's disk cache was cleared by hand. Now sends Cache-Control: no-store. - the lightbox's zoomed image used flex centering (align-items/ justify-content: center) combined with overflow: auto — a well-known trap where the browser centers overflowing content by shifting it, and the leading half of that overflow (here, the top of a zoomed photo) sits outside what the scrollport can actually reach. Reported live as "unusable". Fixed by switching to top/left alignment once zoomed. Co-Authored-By: Claude Sonnet 5 Claude-Session: https://claude.ai/code/session_01TiZG4AuSnxHohQMpwTHTyL

meshbay.git/docs/photos.md, branch 0.8

feat: add Photos group app