Add cribbage for two, three or four players

The whole game: the crib, the cut, the play and the show, pegging on a
board drawn with both pegs so the last score is visible as well as the
total.

Three tables rather than one. Two play head to head with six cards and
lay two away; three play singly with five and lay one, with a fourth
card dealt straight into the crib because three hands cannot fill it;
four play in partnerships pegging on one score, where your partner's
crib is your crib. Every table keeps four cards and every crib holds
four, which is what lets one engine serve all three.

The rule that shapes the code is that a game ends on the point that
reaches the target, mid-count if that is where it falls. Every award
goes through one function that stops the game there and refuses
everything after it, so a non-dealer who counts out wins before the
dealer's hand and crib are counted at all — the show reports those as
never counted rather than adding them on.

A go is called by the engine rather than tapped. The count only rises
within a series, so a hand that cannot play now cannot play later in
it, and there is nothing to decide; the log says who went past.

The opponent works out its lay-away rather than guessing: every way of
keeping four is scored against all forty-six cards that could still be
cut, and what goes to the crib is valued separately and added or
subtracted depending on whose crib it is. It takes 114 games out of 120
against random legal play, from either seat.

teamForSeat now takes the seat count, because cribbage is only a
partnership game at four — reading seat % 2 at a table of three would
have put the first and third players on the same side.

Co-Authored-By: Claude Opus 5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01DCuRESmSZeJoJond43itw2

README.md

@@ -9,7 +9,7 @@ The app shell is complete and every game in the catalogue is playable end to end
 
 | | |
 | --- | --- |
-| **Cards** | Euchre, Kaiser, President, Golf, Wizard, Crazy 8s |
+| **Cards** | Euchre, Kaiser, President, Golf, Wizard, Crazy 8s, Cribbage |
 | **Board** | Sequence, Chess, Checkers, Backgammon, Mastermind, Nine Men's Morris, Pirates and Bulgars, Ta Yü |
 
 Nothing is marked *Coming soon* at the moment, because nothing is waiting. The
@@ -47,7 +47,7 @@ them.
 ## Scorekeeper
 
 **Scorekeeper** on the main menu is a pencil for games the app does not deal —
-darts, cribbage, whatever is actually on the table. It is laid out as the paper
+darts, rummy, whatever is actually on the table. It is laid out as the paper
 it replaces: a column per player with their name at the head, a row per round
 running down the page, and the running total ruled off at the foot.
 
@@ -292,6 +292,8 @@ game:
 - [Golf](docs/RULES-golf.md)
 - [Wizard](docs/RULES-wizard.md)
 - [Crazy 8s](docs/RULES-crazy8s.md)
+- [Cribbage](docs/RULES-cribbage.md) — two, three or four, and **note that four
+  play in partnerships pegging on one score**
 - [Chess](docs/RULES-chess.md)
 - [Checkers](docs/RULES-checkers.md) — **note the caveat about flying kings**
 - [Backgammon](docs/RULES-backgammon.md) — **note that there is no doubling cube**
@@ -318,6 +320,7 @@ game/          rules engines and AI — pure Kotlin, no Android, unit-tested
   golf/        Golf model, scoring, rules, AI
   wizard/      Wizard model, rules, AI
   crazyeights/ Crazy 8s model, rules, AI
+  cribbage/    Cribbage the crib, the play, the show, and a counting AI
   chess/       Chess model, FEN, move generation, search
   morris/      Nine Men's Morris board geometry, mills, rules, search
   checkers/    Checkers board, compulsory captures, crowning, search