Add personalization, outbound feeds, and PWA/push to the web UI

A multi-session build turning Pete's read-only web UI into something people
return to. Five phases, signed-in features keyed off the OIDC subject; anonymous
visitors keep the reverse-chron feed and localStorage-only state.

Phase 1 — per-user read + bookmark state: user_story_state table +
storage/userstate.go; auth-gated /api/read, /api/bookmark, /api/state and a
/bookmarks page; reader.js syncs state server-side for signed-in users. Also
hides the Matrix-posting UI when posting.enabled=false (web-only mode).

Phase 2 — outbound feeds: storage.ListForFeed + web/feed.go hand-build RSS 2.0
(content:encoded) and JSON Feed 1.1 (no new dep); /feed.xml, /feed.json and
per-channel variants; <link rel=alternate> discovery tags.

Phase 3 — "For you" + related: storage/rank.go scores recent unread candidates
by channel/source affinity + recency decay; RelatedStories via FTS5. ForYou rail
+ /for-you page; public /api/related feeds the reader's "You might also like".

Phase 4 — source-health dashboard: source_health table + storage/sourcehealth.go
(RecordPollResult, ListSourceHealth, SourceContentStats), written by the poller;
admin-gated /status page behind web.admin_subs.

Phase 5 — PWA + offline reader + Web Push: root-scoped manifest.webmanifest and
sw.js (app-shell precache, /api/article runtime cache for offline reading,
offline fallback, push/notificationclick handlers); PNG icons from pete.avif;
pwa.js registers the SW and drives a notifications toggle. Web Push adds
webpush-go, a [web.push] config block (pete -genvapid mints VAPID keys), a
push_subscriptions table, auth-gated subscribe/unsubscribe endpoints, and a
digest sender that pings each subscriber "N new stories" past their watermark,
honoring disabled-sources and pruning gone endpoints.

Tests added beside each new storage/web file; go test ./... and go vet clean.

internal/web/static/css/input.css

@@ -330,6 +330,62 @@ html[data-phase="night"] {
     .pete-reader-hint { display: none; }
   }
 
+  /* "You might also like" rail, shown under the article in feed mode. Lives
+     inside the reader's scroll area, below the article card. */
+  .pete-reader-related { width: 100%; margin: 0.85rem auto 0; }
+  .pete-reader-related-title {
+    font-family: "Fredoka", "Nunito", system-ui, sans-serif;
+    font-weight: 700;
+    font-size: 0.95rem;
+    color: #fff;
+    margin: 0 0 0.6rem;
+    text-shadow: 0 1px 2px rgba(0, 0, 0, 0.4);
+  }
+  .pete-reader-related-grid { display: grid; gap: 0.6rem; }
+  .pete-reader-related-card {
+    display: flex;
+    align-items: center;
+    gap: 0.75rem;
+    background: var(--card);
+    color: var(--ink);
+    border-radius: 1rem;
+    border: 2px solid rgba(0, 0, 0, 0.06);
+    padding: 0.6rem;
+    text-decoration: none;
+    transition: transform 0.15s ease, box-shadow 0.15s ease;
+  }
+  .pete-reader-related-card:hover {
+    transform: translateY(-1px);
+    box-shadow: 0 6px 16px rgba(60, 40, 20, 0.16);
+  }
+  html[data-phase="night"] .pete-reader-related-card { border-color: rgba(255, 255, 255, 0.08); }
+  .pete-reader-related-thumb {
+    width: 4.5rem;
+    height: 3.25rem;
+    flex-shrink: 0;
+    object-fit: cover;
+    border-radius: 0.6rem;
+    background: rgba(0, 0, 0, 0.06);
+  }
+  .pete-reader-related-meta { min-width: 0; display: flex; flex-direction: column; gap: 0.25rem; }
+  .pete-reader-related-eyebrow {
+    display: flex;
+    align-items: center;
+    flex-wrap: wrap;
+    gap: 0.4rem;
+    font-size: 0.7rem;
+  }
+  .pete-reader-related-source { font-weight: 700; opacity: 0.7; }
+  .pete-reader-related-headline {
+    font-weight: 700;
+    line-height: 1.25;
+    font-size: 0.92rem;
+    display: -webkit-box;
+    -webkit-line-clamp: 2;
+    -webkit-box-orient: vertical;
+    overflow: hidden;
+  }
+
   /* Grid treatment for stories already read in feed mode: dimmed, with a small
      corner check. Hovering restores full opacity so nothing feels lost. */
   [data-story-card][data-read="1"] { opacity: 0.5; transition: opacity 0.2s ease; }