Restore the Pro Libertate Games title and splash; list Katan under Board Games

The bootstrap rebranded the app to Pilgrims of Katan (WALA-118 review);
the decision is to keep the upstream's own identity instead.

- Title and splash: the upstream originals restored exactly — the Wallace
  tartan splash under the "Pro Libertate Games" uncial wordmark
  (SplashScreen.kt, Tartan.kt), the tartan launcher icon, and the
  Theme.ProLibertateGames window theme. The game screens go back to the
  upstream WallaceGold/WallaceRed accents the tartan is woven from.
- Names and colours: launcher names back to "Pro Libertate Games" /
  "Pro Libertate Games DEV"; the channel colours back to the clan red /
  hunting green setts (resValue tartan_field and friends). The installed
  identity stays ca.wallacenet.pilgrimsofkatan (+ .dev) — that is the
  package, not the brand.
- Catalogue: Katan is listed under Board Games (3-4 players, original
  blurb, no third-party marks) with available = false, so dev builds show
  it as "Coming soon" and a production build hides it until its engine
  and screen land.
- Docs: README/CLAUDE.md/docs/CI.md updated to the restored identity;
  CatalogTest's invariant now names Katan as the one deliberate exception
  rather than asserting nothing is unfinished.

Structural bootstrap untouched: applicationId, OTA repointed at the Gitea
releases, CI workflows, version stamping.

Verified: ./gradlew assembleDebug and testDebugUnitTest green — 628 tests,
0 failures.

Co-Authored-By: Paperclip <[email protected]>

app/src/main/res/drawable/ic_launcher_foreground.xml

@@ -1,23 +1,15 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!--
-  The brand emblem: a hexagonal ring around a solid hexagonal core, in
-  parchment on the brand field behind it (see ic_launcher_background).
-
-  The hexagon is a game tile, not any game's mark — deliberately generic
-  branding for Pilgrims of Katan, carrying no third-party logo or trade dress.
-  Everything sits inside the adaptive icon's safe zone (a centred 66dp circle
-  on this 108dp canvas) so no launcher mask can clip it.
+  Deliberately empty. The icon is the cloth itself, so the adaptive icon's
+  foreground layer carries nothing — anything drawn here would sit on top of the
+  tartan and break the "single square of tartan" idea.
 -->
 <vector xmlns:android="http://schemas.android.com/apk/res/android"
     android:width="108dp"
     android:height="108dp"
     android:viewportWidth="108"
     android:viewportHeight="108">
-    <!-- Ring and core in one even-odd path: outer hexagon, inner hexagon,
-         core hexagon — odd coverage fills, so the ring and the core are drawn
-         and the gap between them stays open to the field showing through. -->
     <path
-        android:fillColor="@color/brand_accent"
-        android:fillType="evenOdd"
-        android:pathData="M84,54 L69,79.98 L39,79.98 L24,54 L39,28.02 L69,28.02 Z M72,54 L63,69.59 L45,69.59 L36,54 L45,38.41 L63,38.41 Z M63,54 L58.5,61.79 L49.5,61.79 L45,54 L49.5,46.21 L58.5,46.21 Z" />
+        android:fillColor="#00000000"
+        android:pathData="M0,0h108v108h-108z" />
 </vector>