Add Kaiser, Crazy 8s and Wizard

Three more card games, engine to screen.

Kaiser: 32-card prairie trick-taking with bidding, the five of hearts
worth five and the three of spades costing three. Bidding is capped at
ten because ten is all a hand can be worth, and a losing score gives the
game a floor — without one a table that keeps bidding and going down
never reaches a result.

Crazy 8s: eights are wild and name the suit in force, which is why the
table states that suit in words rather than leaving it to be read off
the pile. Blocked rounds are scored rather than hanging.

Wizard: the 60-card deck, one more card dealt each round until the pack
runs out, bid your tricks exactly. The shared card model gains WIZARD
and JESTER ranks, so every ordinary deck now builds from Rank.standard
rather than walking the whole enum.

Also fixes a lobby bug this would have hit: hosting seated the
catalogue minimum rather than the table the host had just set up, so a
six-handed game would have been rejected by its own rules engine.

164 engine tests pass locally.

docs/RULES-wizard.md

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+# Wizard — implemented rules
+
+This is the ruleset the engine enforces. Anything marked **toggle** is in the
+game setup screen.
+
+## Table
+
+- 3 to 6 players — **toggle**. Everyone plays for themselves.
+
+## The deck — 60 cards
+
+An ordinary 52-card pack plus **four wizards** and **four jesters**.
+
+## Rounds
+
+Round 1 deals one card each, round 2 deals two, and so on until the pack runs
+out. That is 20 rounds with three players, 15 with four, 12 with five and 10
+with six. **Toggle** to stop after 5 or 10 rounds instead of playing the lot.
+
+After the deal, the next card off the pack is turned for trump:
+
+- an ordinary card — its suit is trump;
+- a **jester** — the round is played with no trump;
+- a **wizard** — the dealer names trump before anyone bids.
+
+In the last round the whole pack has been dealt, so there is no card to turn and
+no trump.
+
+## Bidding
+
+Starting to the dealer's left, each player says exactly how many tricks they
+will take, from none up to the number of cards in hand. Every bid is heard, so
+the later you bid the more you know.
+
+**Screw the dealer — *toggle*, off by default.** The dealer may not name the
+number that would make the bids add up to the tricks available, so at least one
+player at the table is always going to be wrong.
+
+## Play
+
+The player to the dealer's left leads. Follow the led suit if you hold it —
+except that a **wizard or a jester may always be played**, whatever you hold.
+Playing one is how you get out of following.
+
+**What suit is led:**
+
+- an ordinary card leads its suit;
+- a **jester** leads nothing — the suit is set by the next ordinary card;
+- a **wizard** reaching the front means no suit is led at all, and everyone may
+  play whatever they like.
+
+**Who takes the trick:**
+
+1. The **first wizard** played takes it, whatever else is down.
+2. Otherwise the highest trump.
+3. Otherwise the highest card of the led suit.
+4. A **jester** never wins — except a trick of nothing but jesters, which goes
+   to the first one played.
+
+## Scoring
+
+| Result | Score |
+| --- | --- |
+| Bid made exactly | 20, plus 10 for each trick taken |
+| Bid missed | −10 for every trick over or under |
+
+So bidding none and taking none is worth 20; bidding three and taking three is
+worth 50; bidding three and taking one costs 20.
+
+Highest total after the last round wins.
+
+## What the computer opponent does
+
+It counts its expected tricks — a wizard is one, a jester is none, and
+everything else is a fraction depending on how high it is and whether it is
+trump — and bids the nearest number still on offer. In play it chases tricks
+while it is short of its bid, taking them as cheaply as it can, and ducks once
+it has them, leading a jester when it has one to spare.
+
+Over long runs of self-play it lands its bid exactly around half the time,
+against about one in six for random legal play.