Katan: Cities & Knights docs, knight menu for any own knight, tidier player card

Co-Authored-By: Claude Sonnet 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_016eTor2tpxKb4dXbd8RqnvZ

docs/RULES-catan.md

@@ -12,14 +12,27 @@ players, as published.
 The engine is a pure state machine (`CatanRules`) with no Android types, and its
 behaviour is pinned by `CatanBoardTest`, `CatanRulesTest` and `CatanAiTest`.
 
+## Rule sets
+
+A table plays one of two rule sets, chosen on the setup screen
+(`CatanOptions.ruleSet`):
+
+- **Base game** — everything in this document.
+- **Cities & Knights** — the expansion, documented in
+  [RULES-catan-ck.md](RULES-catan-ck.md). It reuses this document's board, setup,
+  building, robber and trade rules and changes or replaces the rest; its state lives
+  behind `CatanState.ck`, which is `null` in the base game.
+
 ## Table
 
+- **Rules — *toggle*.** Base game or Cities & Knights (`CatanOptions.ruleSet`).
 - **Players — *toggle*.** Three or four. `CatanOptions.playerCount`; the engine
   refuses anything else.
 - **Points to win — *toggle*.** Defaults to 10. `CatanOptions.pointsToWin`, at
   least 2. A lower target makes a test game short.
 
-The setup screen exposes both (players: 3 or 4; game to 5, 8, 10 or 12 points).
+The setup screen exposes all three (players: 3 or 4; game to 5, 8, 10 or 12 points in the
+base game, 8, 10, 13 or 15 in Cities & Knights, whose published target is 13).
 
 ## Board
 
@@ -296,6 +309,13 @@ timing rules; Longest Road and Largest Army worth five; victory at ten.
 
 ## Known gaps
 
+- **Longest Road and Largest Army are worth 5 each here.** The published base game awards
+  **2** each (Catan Universe's almanac says so for Largest Army, and the printed rules
+  for both). Cities & Knights scores Longest Road at 2, as printed. Left unchanged in
+  the base game so far; it is a one-constant change in `publicVictoryPoints`.
+- **A bank short of a resource pays nobody that roll**, even when only one player is owed
+  it. The published ruling lets a lone claimant take what is left; Cities & Knights does.
+
 - **No domestic auction or counter-offer.** An offer is addressed to a single
   seat. Open trading to the whole table, and counter-offers, are the obvious next
   step and are not implemented.