chore: remove the image-asset feature (Image widget + kip-plugin image service)

[mairas]

Implements the plan in #107. Removes the imported image-asset feature (upstream Kip #1080/#1081/#1082 → Skip #54/#50/#62) in full.

Why

Signal K has no reusable image/media API to lean on (the Resources API is JSON-only; charts and sk-video serve binary via their own plugin routes). The feature carries a heavy security surface (SVG-upload sanitization, multipart upload, worker pool), and the right long-term shape is a standalone sk-media plugin — mirroring how the Video widget already consumes the external sk-video plugin. So: remove now, recreate later via sk-media. This PR does not build that plugin.

What (4 atomic commits)

1. Client (Closes Remove the Angular image feature (widget + service + Media config UI) #108) — delete the Image widget, ImageAssetService, image config UI, kip-plugin-url.util; un-wire the widget registry, the settings Media tab, the image? config field, the root-modal image tab, the help entry, and the imageWidget icon.
2. Server (Closes Remove the kip-plugin image subsystem (/plugins/kip/images) #109) — delete kip-plugin/src/images/ + its tests; un-wire kip-plugin/src/index.ts (image store init, registerImageRoutes, image imports, orphaned nodePath).
3. Deps (Closes Drop image-only deps (multer, sharp) + e2e image harness #110) — drop multer, sharp, and isomorphic-dompurify (the last was added by the image PR for SVG sanitization and is now orphaned — a refinement over the plan, which named only multer/sharp); delete the image e2e harness.
4. Changelog (Closes Changelog: note image feature removal #111).

Kept (verified intact)

signalk-plugin-url.util.ts (used by sk-video + the kip history client), all Video/sk-video code, all history/series code.

No migration

A dashboard with an existing Image widget degrades to a graceful "failed to load" placeholder — WidgetService.getComponentType() returns undefined for an unknown selector and widget-host2 guards on it (sets loadFailed), so no crash and no config-upgrade step is needed. Documented in the changelog.

Verification

• npm run lint clean; npm run build:dev clean (full type-check).
• npm run build:plugin clean; npm run test:plugin 60/60 pass.
• Grep confirms zero dangling image references and no remaining spec references the deleted code (webapp vitest runs in CI).

Closes #107. Follow-ups (separate): file sk-media tracking issue; reconcile #106; update #76.

🤖 Generated with Claude Code

https://claude.ai/code/session_018zURudCY3TTRcNd2acknJ9

[mairas]

Review synthesis

Independent 3-lens review (completeness / keep-list regression / adversarial), each a fresh-context agent, with adversarial verification of blocking findings. 0 blocking, 0 high.

Findings (both fixed, folded into the atomic commits — see force-push below):

• medium — orphaned heic-convert dep. An image-only dependency (HEIC→JPEG transcode, consumed only by the deleted image-processing.ts) that I missed alongside multer/sharp/isomorphic-dompurify. Now dropped in the deps commit; zero heic references remain and it's gone from the lockfile.
• nit — stale doc comment. The kept signalk-plugin-url.util.ts header still named "the image-asset client" as a former consumer. Reworded to kip-series-api-client.service + the sk-video clients.

Keep-list verified intact by the review: signalk-plugin-url.util.ts + its real consumers (video widget, video-camera-setup) compile; the full Video/sk-video feature (incl. piexifjs snapshot path) is present; kip-plugin HistorySeriesService / sqlite storage / History-API provider registration / /series routes are intact (plugin build exit 0); and the widget-registry / options-tabs / root-modal splices are structurally clean (production AOT build succeeded). Adversarial lens constructed no runtime/CI failure — a saved image-widget instance degrades to loadFailed, not a crash.

Force-push note: the branch was rewritten (1ca3a636 → 4cc8e3a6) to fold these two fixes into their proper units (deps / client-cleanup) rather than append a patch commit — keeping the 4-commit history free of a superseded intermediate state. Diff is otherwise unchanged.

Re-verified locally: lint clean, build:dev clean, build:plugin clean, test:plugin 60/60.