Fix four rules and modelling defects found in review

TDA Rule 47 — cumulative incomplete raises:
A boolean could not express "facing at least a full raise since acting", so
several short all-ins that together reached a full raise failed to reopen
betting. Seat now records lastActedAtBet (the currentBet when it last acted);
mayRaise() reopens when currentBet - lastActedAtBet >= minRaiseSize. This
subsumes the single-incomplete-raise case, so the hasActed reset in apply() is
gone.

TDA Rule 20 — odd chips:
Split-pot remainders were awarded in seat-list order. They now go to the first
winning seat clockwise from the button. The old test also never produced an odd
pot (20 chips heads-up), so it only ever proved an even split; it now builds a
genuinely odd 25-chip pot via a folded small blind and asserts which seat takes
the extra chip.

OpponentModel skipped events across hands:
It inferred a new hand from a shrinking history, but history is cleared each
hand: having consumed 3 events, first observing the next hand at 4 events left
4 < 3 false and silently dropped the first three. observe() now takes an
explicit handNumber, exposed via DecisionContext and Table.handNumber.

PreflopChart percentile semantics:
The 169 classes were ranked equally, but they are not equally likely — a pair is
6 of 1326 combinations, suited 4, offsuit 12. "Top 12%" therefore meant 12% of
classes, not of dealt hands, so looseness did not mean what it claimed.
Percentiles are now weighted by combination count.

Tests: 30 -> 37. Each new test was verified to fail with its fix reverted.
Skill gradient still monotonic: 85.9 / 79.8 / 17.4 / -183.1 bb/100 over 50k
hands, chips conserved on both tables.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

CLAUDE.md

@@ -56,10 +56,24 @@ export JAVA_HOME="/Applications/Android Studio.app/Contents/jbr/Contents/Home"
 
 - Evaluator: verified exhaustively against published frequencies for all
   2,598,960 five-card hands. ~24M evals/sec.
-- Engine: chip-conserving; side pots, odd-chip splits, uncalled-bet refunds, and
-  incomplete (short all-in) raises all covered by tests.
-- Bots: skill gradient **passes** monotonically (73.9 / 53.9 / 27.6 / −155.4
+- Engine: chip-conserving. Covered by tests: side pots, uncalled-bet refunds,
+  action order, malformed agent output, **TDA Rule 47** (incomplete raises do not
+  reopen betting, but several that cumulatively reach a full raise do), and
+  **TDA Rule 20** (odd chip to the first winner left of the button).
+- Bots: skill gradient **passes** monotonically (85.9 / 79.8 / 17.4 / −183.1
   bb/100 at 50k hands).
+
+### Rules invariants that are easy to get wrong
+
+- Reopening betting cannot be a boolean. `Seat.lastActedAtBet` records the bet
+  level a player last acted at; betting reopens when `currentBet - lastActedAtBet
+  >= minRaiseSize`. Several short all-ins can reach that together.
+- `PreflopChart` percentiles are weighted by **combination counts** (pair 6,
+  suited 4, offsuit 12, total 1326), so "top 12%" means 12% of *dealt hands*, not
+  12% of the 169 classes.
+- Anything consuming `DecisionContext.history` across hands must key off
+  `handNumber`. History is cleared each hand, so a size comparison silently drops
+  events.
 - Known-imperfect: win-rate magnitudes are still ~10x realistic, and several
   profiles are looser than their labels (the Rock plays ~38% VPIP, should be
   ~12%). Tuning is the open work.