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Add LLWS 20-team double-elimination bracket 1bd23a4419

The Little League Baseball World Series runs two independent 10-team
double-elimination brackets — United States and International — each
producing a side champion, then a World Championship game and a
Consolation Third Place game between the side runners-up. 38 games in
all. No existing template could express it: every one is single
elimination, at most with a bolted-on third-place game.

Adds the llws_20 template plus dedicated generation and advancement,
following the same bespoke-routing pattern afl_10 and nba_20 use rather
than the generic ceil(matchNumber / 2) advancement.

The core of the change is loser routing. In the winners bracket a loss
is not an elimination — it drops the team into the elimination bracket
at a specific slot, including the deliberate cross-overs the official
bracket uses (Elimination Round 1 pairs L4/L6 and L2/L8; Elimination
Round 3 pairs each semifinal loser with the winner from the opposite
half). In the elimination bracket a loss is final. Matching the official
modified double-elimination format, there is no "if necessary" game: the
winners-bracket champion is eliminated if it loses the side
championship, dropping to the consolation game.

Rounds are shared across both sides, U.S. taking the low match numbers
and International the high ones, so the scoring config stays one entry
per stage. The existing phases/groups display machinery splits them back
apart into United States / International / Championship tabs.

Scoring lands on exactly 8 point-earning teams, which is the field size
when Elimination Round 4 begins: the two finals decide 1st–4th,
Elimination Final losers take 5th–6th, and Elimination Round 4 losers
7th–8th. 3rd and 4th are distinct because the consolation game is real,
and 5–8 splits into two two-team tiers so surviving Elimination Round 4
is worth more than losing it.

Also:

- Adds an optional nonScoringWinnerFloor to BracketRound. The engine
  hardcoded a 5th-place floor for winners of non-scoring rounds feeding
  a scoring one, which is wrong inside a losers bracket where a win can
  guarantee only 7th. Opt-in, so no existing template changes behavior.

- Fixes TabbedBracketLayout's mobile path, which built its match map
  unfiltered and so would have merged U.S. and International games into
  one column. No-op for NCAA and NBA, whose groups already cover every
  match in their phases.

- Rewrites the LLWS Monte Carlo simulator, which still modelled the
  retired pool-play format (5 teams per pool, then a 4-team bracket per
  side) and no longer described the tournament being scored. It now runs
  the real 10-team double elimination and splits the 5–8 probabilities
  into the correct tiers instead of one even four-way split. Legacy
  "US:A"/"Intl:B" externalIds are still accepted, read as the side
  alone, so seasons configured for the old format keep loading.

Tests replay all 38 games through the pure advancement resolver and
assert each one against the feed labels printed on the official bracket.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EAxqBVzfmKJe6WQ6VF9guj

Fix final rankings for double-elimination brackets

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37af2f1fc3

Review of the llws_20 bracket turned up two display bugs in the shared
ranking code, both triggered by the template setting loserFeedsInto on
every winners-bracket round.

findConsolationRound took the FIRST round with loserFeedsInto and
treated its target as a third-place game. That is sound for fifa_48,
whose only such round is the Semifinals, but llws_20 uses loserFeedsInto
to route losers into the elimination bracket — so "Elimination Round 1"
was being read as the consolation game. Its four matches were then
placed as exact positions inside the Opening Round tier, corrupting the
final rankings list. A consolation round now has to be terminal: its
winner plays no further game, which is precisely what lets its result
split two exact positions.

The rank walk also advanced by a round's match count on the assumption
that every match places its loser. That holds in single elimination and
must be kept for undecided rounds — four semifinalists occupy positions
1-4 whether or not the games have been played — but a winners-bracket
loss places nobody, since the loser drops into the elimination bracket
and is ranked by whatever knocks them out later. Those rounds consumed
positions they never filled, so a 20-team bracket ranked its last teams
T23. Rounds whose losers are placed later now consume nothing, leaving
LLWS at 1, T2, 3, 4, T5, T7, T9, T13, T17 for the full 20-team field.
Single-elimination templates are unaffected; afl_10's sub-8th ranks were
inflated the same way and are now correct too.

Also from review: the llws_20 participant labels were 21-24 characters
in an 80px fixed-width admin column and would have wrapped to three
lines across all 20 rows. Shortened them and widened the column.

Tests play a full 20-team tournament through the real advancement map
and assert the resulting rank labels.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EAxqBVzfmKJe6WQ6VF9guj