Drop-folder image flow + web image preparer

- Add web-image-prep/: self-contained HTML5 image preparer with
  perceptual Oklab 3-colour quantisation, Floyd-Steinberg/Atkinson/
  Bayer dither, all supported tag profiles, BMPs that match the FAP
  reader exactly. Auto-deployed to GitHub Pages.
- Add 'Set Image' under Targeted Payloads. Lists every BMP in
  apps_data/tagtinker/dropped/, scrolls long names, marks foreign-
  resolution files with a '~' prefix.
- Stream-time nearest-neighbour rescaling so any BMP can target any
  tag at any page; image options screen is now Page-only.
- Remove Phone Sync menu and the Android companion app: replaced by
  the browser preparer + drop folder.
- Static, IR-friendly transmit screen ('Tinkering Tag', point hint,
  3-dot loader, 'Flipped ;)').

.github/workflows/pages.yml

@@ -0,0 +1,37 @@
+name: Deploy Image Prep to GitHub Pages
+
+on:
+  push:
+    branches: [main]
+    paths:
+      - "web-image-prep/**"
+      - ".github/workflows/pages.yml"
+  workflow_dispatch:
+
+permissions:
+  contents: read
+  pages: write
+  id-token: write
+
+concurrency:
+  group: "pages"
+  cancel-in-progress: false
+
+jobs:
+  deploy:
+    environment:
+      name: github-pages
+      url: ${{ steps.deployment.outputs.page_url }}
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+      - name: Configure Pages
+        uses: actions/configure-pages@v5
+      - name: Upload artifact
+        uses: actions/upload-pages-artifact@v3
+        with:
+          path: web-image-prep
+      - name: Deploy
+        id: deployment
+        uses: actions/deploy-pages@v4