Rebuild both UIs on the Cinder design (#10)

Implements the **Cinder** design (Claude Design doc `cfa39183`) across both UI surfaces, self-hosts the fonts it depends on, and writes down the two documents that keep the result maintainable.

## What changed

**Web UI** — rebuilt on the design's visual language: editorial serif, containerless sheets divided by ash hairlines, one 760px measure, no radii and no shadows. The organising rule is that *heat is typographic*: only a series with an unread chapter is crimson (title on an ember underline, cover foot rule, `Ch N out`, play icon), and favourites get brass rather than borrowing the accent. Both states hang off two classes on the `<article>` (`is-new`, `is-dim`), so sub-elements inherit the state instead of re-deriving it.

The six-cell action strip is `flex-basis: 100%` inside the row, which is what lets one piece of markup be a full-width strip with 46px thumb targets on a phone and a group of 40px squares beside the row on a desktop — no duplicate template branches. Icons moved to a sprite (`templates/icons.html`); htmx-swapped cards reference the page's symbols, so a row no longer carries a screenful of inline SVG.

**Userscript panel** — repainted in the same tokens. The panel and the web UI are the same product on the same phone, and the old purple-on-charcoal panel read as a different application once the web UI moved. Structure, ids and classes are untouched, and the edge tab keeps its geometry, `touch-action` and `#hit` sizing.

**Fonts are self-hosted** — five latin-subset woff2 files (~120 KB) embedded via the existing `//go:embed static`. Loading them from Google would lose the design's character exactly where it is used most: Bromite users routinely block Google's font domains, and the backend is reachable over a LAN with no internet route. `staticHandler` registers the `.woff2` MIME type, which Go's table lacks and the scratch image has no `/etc/mime.types` for.

**Docs** — `docs/design-system.md` records the rules a stylesheet cannot state (what the ember is reserved for, why light mode is a re-tuning rather than an inversion, which details are load-bearing) so a future agent does not re-derive them from the CSS. `REDEPLOY.md` covers the operation actually performed every time, which `DEPLOY.md` reduced to two lines.

## Commits

Each is one logical change and builds on its own:

| | |
|---|---|
| `4d69e54` | `listView.NewCount` — data for the Updated badge, no markup |
| `e940b96` | Web UI rebuilt on Cinder (CSS, templates, sprite, `filter.js`) |
| `686fcc1` | Userscript panel repainted in the same tokens |
| `ce7e93d` | Self-hosted webfonts + `.woff2` MIME registration |
| `a547cc9` | `docs/design-system.md` |
| `b20ecf1` | `REDEPLOY.md` |

## Verification

- `go test ./...` — 187 pass. Userscript logic tests — 14 pass.
- Screenshotted at 390px and 1180px, in dark and light, across All / Archived / Finished / empty / chapter-form / confirm-row.
- Fonts: a run with `fonts.googleapis.com` and `fonts.gstatic.com` blocked still reports all five faces `loaded`; served as `200 font/woff2`.
- The three `REDEPLOY.md` backup/restore commands were run, not assumed. `:ro` on the source volume fails (`unable to open database file` — WAL needs to create `-shm`), and a restored file lands root-owned while the container runs as uid 65532, so reads succeed and writes fail. Both are documented with the reason.

## Note for the reviewer

The panel restyle is token-level only: the design doc covers the web UI, so the panel's *structure* has no reference to follow and was deliberately left alone.

Deploying this needs a rebuild — templates, CSS and fonts are `//go:embed`ed, so pulling alone changes nothing.

Reviewed-on: #10
Co-authored-by: Sulthan Zaki <sultankiki05@gmail.com>
Co-committed-by: Sulthan Zaki <sultankiki05@gmail.com>

backend/templates/app.html

@@ -7,19 +7,29 @@
   <meta name="color-scheme" content="dark light">
   <title>mangaBookmark</title>
   <link rel="stylesheet" href="/static/style.css">
+  <link rel="preload" href="/static/fonts/instrument-serif-400-latin.woff2" as="font" type="font/woff2" crossorigin>
+  <link rel="preload" href="/static/fonts/ibm-plex-mono-500-latin.woff2" as="font" type="font/woff2" crossorigin>
   <script src="/static/htmx.min.js" defer></script>
   <script src="/static/filter.js" defer></script>
 </head>
 <body>
+{{template "icons" .}}
+<div class="sheet">
   <header class="topbar">
-    <h1>mangaBookmark</h1>
+    <h1 class="brand">manga<em>Bookmark</em></h1>
     <form method="post" action="/logout">
       <button type="submit" class="ghost">Log out</button>
     </form>
   </header>
 
-  <input id="search" class="search" type="search" placeholder="Search titles…"
-         autocomplete="off" aria-label="Search titles">
+  {{/* Search sits above the tabs on a phone and folds into the tab row on a
+       wider screen — one flex container, order swapped in CSS. */}}
+  <div class="chrome">
+  <div class="searchbar">
+    <svg viewBox="0 0 24 24" aria-hidden="true"><use href="#i-search"/></svg>
+    <input id="search" class="search" type="search" placeholder="Find a title"
+           autocomplete="off" aria-label="Search titles">
+  </div>
 
   <nav class="tabs" role="tablist">
     <a role="tab" href="/?tab=all" class="{{if eq .Tab "all"}}active{{end}}"
@@ -27,7 +37,8 @@
        hx-push-url="/?tab=all" hx-on::after-request="setActiveTab(this)">All</a>
     <a role="tab" href="/?tab=new" class="tab-new {{if eq .Tab "new"}}active{{end}}"
        hx-get="/ui/list?tab=new" hx-target="#list" hx-swap="innerHTML"
-       hx-push-url="/?tab=new" hx-on::after-request="setActiveTab(this)">Updated</a>
+       hx-push-url="/?tab=new" hx-on::after-request="setActiveTab(this)">Updated{{if .NewCount}}
+      <span class="count">{{.NewCount}}</span>{{end}}</a>
     <a role="tab" href="/?tab=fav" class="{{if eq .Tab "fav"}}active{{end}}"
        hx-get="/ui/list?tab=fav" hx-target="#list" hx-swap="innerHTML"
        hx-push-url="/?tab=fav" hx-on::after-request="setActiveTab(this)">Favourites</a>
@@ -38,20 +49,23 @@
        hx-get="/ui/list?tab=finished" hx-target="#list" hx-swap="innerHTML"
        hx-push-url="/?tab=finished" hx-on::after-request="setActiveTab(this)">Finished</a>
   </nav>
+  </div>
 
   {{if .Recent}}
   <section class="recent">
     <h2>Continue reading</h2>
     <div class="recent-strip">
       {{range .Recent}}
-      <a class="recent-card" href="{{.ContinueURL}}" target="_blank" rel="noopener noreferrer">
+      <a class="recent-card {{if .HasNewChapter}}is-new{{end}}" href="{{.ContinueURL}}"
+         target="_blank" rel="noopener noreferrer">
         <span class="recent-cover">
           {{if .Cover}}<img src="{{.Cover}}" alt="" loading="lazy">
-          {{else}}<span class="cover-blank" aria-hidden="true">{{.Initial}}</span>{{end}}
-          {{if .HasNewChapter}}<span class="new-ribbon new-ribbon-sm">New</span>{{end}}
+          {{else}}<span class="monogram" aria-hidden="true">{{.Initial}}</span>{{end}}
+          {{if .HasNewChapter}}<span class="foot-rule"></span>
+          {{else if .Favorite}}<span class="foot-rule brass"></span>{{end}}
         </span>
         <span class="recent-title">{{.Title}}</span>
-        <span class="recent-chapter">Ch {{.LastChapter}}</span>
+        <span class="recent-chapter">Ch {{.LastChapter}}{{if .HasNewChapter}} · New{{end}}</span>
       </a>
       {{end}}
     </div>
@@ -61,6 +75,7 @@
   <main id="list" class="list">
     {{template "list" .}}
   </main>
+</div>
 </body>
 </html>
 {{end}}