feat(site): phase 17 - per-game module pages, /runicnpc/, and checkTerms over the built site

PLAN.md §16 phase 17, built on the org lead's answers of 2026-10-22,
recorded as D75-D79 (count of record 79).

- D75: core marketing pages describe what a game module adds in core's
  words. "Game intelligence" became "What a game module adds"; each
  game's own list moved to src/data/games/ and renders only on the new
  /modules/uo/ and /modules/rust/. /modules/ is a card per game.
- The page-side capability check is per game (assertGameCoverage), the
  item phase 13 moved here.
- D76: the homepage keeps its game screenshot, labelled. screens.mjs
  entries may carry `game` (D67); Screenshot.astro and the app grid
  print the game's name and mark the figure data-game.
- D77: /app/ describes the Rust screens (released the same day).
- D78: /runicnpc/, the standalone page, is in the header and footer;
  the narrow header was re-measured so five links keep two rows.
- D79: checkTerms.mjs --built reads every built page's visible text
  after the build; game routes and data-game elements allow their
  game's words. Proven against ten plants. Still the twelfth check.
- Re-read fixes: /architecture/'s "two machines is also the maximum",
  Discord "guild" on /integrations/, and collection.mjs against what
  Steam sign-in and the Rust module keep (PLAY_DATA_SAFETY.md
  regenerated; the Play answers are unchanged).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01E14m6SuuY6i1vASFeGDBeY

src/components/app/Screenshots.astro

@@ -1,5 +1,6 @@
 ---
 import { screensOf, PHONE } from '../../data/screens.mjs';
+import platform from '../../data/platform.json';
 
 /**
  * The app's screenshot strip. Reserved in phase 5 (D26), filled in phase 9.
@@ -45,7 +46,7 @@ const shots = screensOf('phone');
 
       <ul class="shots__grid">
         {shots.map((shot) => (
-          <li class="shots__item">
+          <li class="shots__item" data-game={shot.game}>
             <img
               src={`/screens/${shot.id}.webp`}
               alt={shot.alt}
@@ -54,7 +55,10 @@ const shots = screensOf('phone');
               loading="lazy"
               decoding="async"
             />
-            <p class="shots__caption">{shot.caption}</p>
+            <p class="shots__caption">
+              {shot.game && <span class="shots__game">{platform.games[shot.game].name}</span>}
+              {shot.caption}
+            </p>
           </li>
         ))}
       </ul>
@@ -91,6 +95,19 @@ const shots = screensOf('phone');
     box-shadow: var(--shadow-card);
   }
 
+  /* The game's name on a game's screen (D67), as Screenshot.astro prints it. */
+  .shots__game {
+    display: inline-block;
+    margin-right: 0.5rem;
+    padding: 0.05rem 0.55rem;
+    border: 1px solid var(--line);
+    border-radius: var(--radius-pill);
+    color: var(--muted);
+    font-size: 0.74rem;
+    letter-spacing: 0.04em;
+    white-space: nowrap;
+  }
+
   .shots__caption {
     margin: 0.85rem 0 0;
     color: var(--dim);