feedback7 R22-FIELDS: the path tie-break never wades into more 深水区 than the official route — on 战场#08(下半) the patrolling 铳 / 卢西恩 take the official upper road from (3,9) to (2,3) again (GitHub #375); golden: boss-boss_2-pair, coop2-ABYSS-10-boosted

GitHub #375 (FrogThai): 「水图boss会从下面这条路往蓝门走，实际应该从上路走」. The walking leaders of 战场#08(下半) 涨潮控制
(act2autochess_m04) are 铳 (level_act1autochess_h07_02 route 6; the Hidden Core 铳 on act1autochess_h08_02's patrol
routes) and 卢西恩 (act2autochess_h07_05 route 8): PATROL_MOVE (3,9) → (2,3) → (5,9). Measured (notes repro-375.mjs):
ours 「3,9 2,9 2,6 4,6 4,4 2,4 2,3」 — the lower road through the 深水区 (3,6) / (4,6) — against the official SPFA
「3,9 5,9 5,4 2,4 2,3」 along row 5 with one 深水区 (5,6); the mirrored (3,11) → (2,17) split the same way.
Cause: grid.js _buildField takes the blockable-ground preference pointer (user playtest #2) when its route crosses
strictly fewer non-blockable tiles; 深水区 is non-blockable itself (no deployment), so the lower road counted 2 against
the upper road's 3 (two floor tiles and one water tile) and won. Official pathfinding is the plain 4-neighbour SPFA
(research 08 §3.1). Now the preference pointer is taken only when its route also crosses no more 深水区 than the official
pointer's (a per-tile `deep` count beside `cost`, start excluded). Rule from the Grok triage (scratch-i1b/375.patch),
re-implemented with a precomputed Grid.deepWater mask (terrain 'deepsea': tile_deepsea and tile_deepwater).

Scope (notes dump-fields.mjs / check-official.mjs, every stage × normal / 联防 / boss rect × every walkable
destination): 48 fields change, only on the two water maps (act2 m04 boss field; the inactive act1 m05), 149 pointers,
every one back to the official pointer. The 21 accepted DEVIATIONS (战场#01 / #02 floor, #07, the inactive #05's 7
water-avoiding routes) are unchanged, as are all 154 audited gate routes and data/stages.json's groundPaths
(tools/build-data.mjs --offline into a scratch dir: every data file identical). Other boss-field preference routes of
m04 that cross fewer 深水区 than the official one stay.

Tests: test/sim/pathing-official.test.js — two new #375 tests (the four patrol legs equal the pure official waypoints;
in a real battle the 铳 climbs to row 5 and steps on the 深水区 (5,6) only), both failing on the parent;
test/sim/pathing-crosscheck.test.js — the independent reference port gets the same 深水区 rule (it flagged both the
patrol leg and a random-crate normal-field route of act2 m04 until then); test/sim/pathing-blockable.test.js — the WALK-leg
audit compares with the equal-length routes that cross no more 深水区 than ours (the 14 accepted arena exceptions
unchanged). Grid-related suites 777/777.

Golden:
- fields boss-boss_2-pair (铳 pair on act2autochess_m04, act1autochess_h07_02): the two 铳 patrol the upper roads;
  leader left 5311560 → 5301010, p1 damage up / p2 down, deaths 0 / 2 → 1 / 3; still 8 / 8 kills.
- matches coop2-ABYSS-10-boosted (act2 m04; Final Assault 卢西恩, Hidden Core 铳): still cleared, team LP 800 → 615. The
  bots' operators stand on the lower rows (the same tiles as before); with the leaders on the upper road the Final
  Assault lasts 335 game s instead of 247 and the Hidden Core 638 instead of 190, both past the 150 real-second mark:
  the overtime drain takes 17 + 168 LP (none before), no leak.

test/sim/pathing-official.test.js

@@ -1,7 +1,8 @@
 // Official route shapes (community report after 0.1.0, D5: on 战场#04 活性源石 the lower-gate enemies walked two tiles
 // straight left of the red gate and then straight up, instead of crossing diagonally from the 4th row to the 3rd as in
 // the official game). grid.js keeps the official flow field (research 08 §3.1) unless the blockable-ground preference
-// route of user playtest #2 (0.1.0's) crosses strictly fewer non-blockable tiles (floor, gates) — a segment that only
+// route of user playtest #2 (0.1.0's) crosses strictly fewer non-blockable tiles (floor, gates) and no more 深水区
+// (GitHub #375) — a segment that only
 // brushes a floor tile's corner does not cross it. Audit: every stage (active or not) × gate × field against the pure
 // official algorithm; the routes that still differ are listed, each avoiding floor the official route walks over.
 import { test } from 'node:test';
@@ -127,6 +128,43 @@ test('audit: every route of every stage (11, active or not) × gate × field is
   assert.equal(official, stages.length * legs.length - seen.size);
 });
 
+// GitHub #375 (FrogThai: 「水图boss会从下面这条路往蓝门走，实际应该从上路走」): on 战场#08(下半) 涨潮控制 the patrolling leaders
+// (铳 — level_act1autochess_h07_02 route 6 —, 卢西恩 — act2autochess_h07_05 route 8: PATROL_MOVE (3,9) → (2,3) → (5,9))
+// took the lower road (3,9) → (2,3) through the two 深水区 tiles (3,6) / (4,6) — one floor tile fewer than the official
+// upper road along row 5, which crosses one water tile. The tie-break may not wade into more 深水区 than the official
+// route (grid.js), so these legs are official again.
+test('#375 战场#08(下半): the (3,9) → (2,3) patrol leg stays on the official upper road', REAL, () => {
+  const sid = 'act2autochess_m04';
+  const g = stageGrid(sid, GEO.BOSS_RECT), pure = stageGrid(sid, GEO.BOSS_RECT, true);
+  for (const [s, e, wp] of [
+    [[3, 9], [2, 3], '3,9 5,9 5,4 2,4 2,3'],
+    [[3, 11], [2, 17], '3,11 5,11 5,16 2,16 2,17'],
+    [[3, 10], [2, 3], '3,10 5,9 5,4 2,4 2,3'],
+    [[4, 10], [3, 9], '4,10 3,9'],
+  ]) {
+    assert.deepEqual(g.waypoints(s[0], s[1], e[0], e[1]), pure.waypoints(s[0], s[1], e[0], e[1]), `(${s}) → (${e})`);
+    assert.equal(str(g.waypoints(s[0], s[1], e[0], e[1])), wp);
+  }
+});
+
+test('#375 real battle (act2 m04, 铳 on act1autochess_h07_02): the patrol walks row 5 to (2,3) and steps on one 深水区 only', REAL, () => {
+  const h = makeBattle({ kind: 'boss', stageId: 'act2autochess_m04', waveTemplate: 'act1autochess_h07_02', units: [], autoFinish: false, timeLimit: 120,
+    sharedBoss: { hp: 1e12, maxHp: 1e12, damage(pid, n) { this.hp -= n; } } });
+  const rows = getDefaultSource().getStage('act2autochess_m04').raw.rows;
+  const tiles = [];
+  h.b.on('tick', () => {
+    const e = h.b.enemies.find((u) => u.alive && u.defId === 'enemy_9017_achunt');
+    if (!e) return;
+    const k = `${Math.round(e.y)},${Math.round(e.x)}`;
+    if (tiles[tiles.length - 1] !== k) tiles.push(k);
+  });
+  assert.ok(h.runUntil(() => tiles.includes('2,4'), 60), `reaches (2,4): ${tiles.join(' ')}`);
+  const upTo = tiles.slice(0, tiles.indexOf('2,4') + 1);
+  assert.deepEqual(upTo.slice(0, 4), ['4,10', '3,9', '4,9', '5,9'], `up to row 5 first: ${upTo.join(' ')}`);
+  const water = upTo.filter((k) => { const [r, c] = k.split(',').map(Number); return rows[r][c] === 'd'; });
+  assert.deepEqual(water, ['5,6'], `深水区 stepped on: ${water.join(' ')} (route ${upTo.join(' ')})`);
+});
+
 test('D5: an operator on (9,9), (9,8) or (10,8) blocks the lower-gate enemy on the official diagonal', REAL, () => {
   const guard = chessRec({ id: 't_guard', profession: 'WARRIOR', stats: { atk: 0, blockCnt: 3, maxHp: 1e6 }, skill: null });
   const walker = enemyRec({ key: 'enemy_walker', hp: 1e6, speed: 1 });