fix: cap junction mitres at the visual limit and drop foreign-sector pair patches (#309)

Вылет mitre ограничен VISUAL_MITRE_LIMIT = 1.5·max(h): длиннее — плоская
фаска перпендикулярно направлению вершины (chamferApex), в парных патчах и
в веерах узлов. Узлы ≥3 канонических лучей закрываются веерами
junctionNodeGeometry прямо в linearWallJoinPatches: парный патч живёт в
секторе, противоположном своей паре, и красил ступень поверх тонких полос
(крест 15/15/30/30 из отчёта владельца). Прямые углы (вылет 1.41h)
байтово прежние. Механизм #249 (MULTI_WALL_JOIN_LIMIT,
multiWallBevelCutsAt, mitre контуров комнат) не тронут.

Юниты формы на фикстуре трёх узлов владельца + контрактный детектор дыр;
4 новых мутанта, краснота каждого проверена исполнением. Матрица golden 46:
три новые сцены junction-309-{step,spike,hump}-dark.

Issue: #309
User-Visible: yes

docs/CHANGELOG.md

@@ -2,6 +2,13 @@
 
 ## Unreleased
 
+- Wall junctions no longer sprout teeth: a mitre apex is limited to 1.5
+  half-depths and anything longer is closed with a flat drafting chamfer, so
+  acute pairs lose their tails, thick multi-wall nodes lose their peaks, and
+  mixed-thickness crosses no longer show a step in a foreign quadrant. Square
+  corners are untouched
+  ([#309](https://github.com/Matysh/houseplan-card/issues/309)).
+
 - The active wall chain keeps its axis and node markers visible on already
   placed segments while drawing. The chain ink now paints above the wall
   masonry (and below the snap overlay), so each click no longer buries the

docs/CHANGELOG.ru.md

@@ -8,6 +8,12 @@
 
 ## Не выпущено
 
+- Стыковочные узлы больше не выпускают зубцы: вылет mitre ограничен
+  1.5 полутолщины, всё длиннее закрывается плоской чертёжной фаской — у
+  острых пар исчезают хвосты, у толстых многолучевых узлов пики, а кресты
+  смешанных толщин теряют ступеньку в чужом квадранте. Прямые углы не
+  изменились ([#309](https://github.com/Matysh/houseplan-card/issues/309)).
+
 - Во время рисования цепочки стен осевая линия и узлы остаются видимыми на уже
   поставленных сегментах. Разметка цепочки теперь рисуется поверх кладки стен
   (и под снап-оверлеем), поэтому каждый клик больше не прячет жёлтую ось под

docs/WALL-THICKNESS.md

@@ -203,6 +203,21 @@ bound» is machine-checked by `junctionContractHoles` in tests and the
 `smoke_junction_holes` wiring probe. Degenerate zero-area rings left by
 coincident chords are dropped.
 
+**Visual mitre limit (#309, owner decision 2026-08-25).** A mitre apex may
+protrude at most `VISUAL_MITRE_LIMIT = 1.5` maximal half-depths from the node
+(a square corner of equal depths peaks at ~1.41·h, so right and obtuse
+corners are byte-identical); a longer apex is closed with a flat chamfer
+perpendicular to the apex direction at the limit (`chamferApex`). The rule
+applies to both the junction fans and the pair patches of
+`linearWallJoinPatches`; `MITRE_LIMIT = 4` survives only as the sanity bound
+for candidate construction. At a node of three or more canonical rays the
+pair patches are not built at all: a pair patch lives in the sector OPPOSITE
+its pair and painted a step over the thinner strips owning that sector (the
+15/15/30/30 cross of the owner report) — such nodes are closed with the same
+sector fans via a local multi-wall node map inside `linearWallJoinPatches`.
+The #249 machinery (`MULTI_WALL_JOIN_LIMIT = 1.25`, `multiWallBevelCutsAt`,
+room-contour mitres) is untouched.
+
 **Hatch density is physical (#230).** The pattern step is a distance on the
 plan, not a count of coordinate units: `wallHatchStepUnits(cellCm)` returns
 `8 × (5 / cell_cm)`, which is 9.6 cm at every grid scale and exactly the

docs/images/screenshots.json

@@ -2,7 +2,7 @@
   "version": 1,
   "fixture": "synthetic-only",
   "chromium": "151.0.7922.34",
-  "sourceFingerprint": "e9ccc3f9aecc3ce4de775233b9e31aedca19c8a474d9839d96a82ebd79d0f272",
+  "sourceFingerprint": "81255e1bea5fc85e11741baf7a296d033ec81cce05dede922d60924597ea605a",
   "captureScriptSha256": "ce2e9542fed9dade3085be87d16f69adb2ac8262893ad78ad966b1b9673f2983",
   "command": "npm run build && node demo/docs/capture.mjs",
   "scenarios": {
@@ -14,7 +14,7 @@
       },
       "theme": "dark",
       "language": "en",
-      "sourceSha256": "e9ccc3f9aecc3ce4de775233b9e31aedca19c8a474d9839d96a82ebd79d0f272",
+      "sourceSha256": "81255e1bea5fc85e11741baf7a296d033ec81cce05dede922d60924597ea605a",
       "imageSha256": "0ca982495a7749907c48ebbddfd089c54385a4347f79f64e94af2c5a8d5c03eb"
     },
     "view-touch": {
@@ -25,7 +25,7 @@
       },
       "theme": "dark",
       "language": "en",
-      "sourceSha256": "e9ccc3f9aecc3ce4de775233b9e31aedca19c8a474d9839d96a82ebd79d0f272",
+      "sourceSha256": "81255e1bea5fc85e11741baf7a296d033ec81cce05dede922d60924597ea605a",
       "imageSha256": "1c8e28ff34736b936ba7c9ec047d1da27aaf6fbb01411155f2d5c05282c02c41"
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     "space-create": {
@@ -36,7 +36,7 @@
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       "language": "en",
-      "sourceSha256": "e9ccc3f9aecc3ce4de775233b9e31aedca19c8a474d9839d96a82ebd79d0f272",
+      "sourceSha256": "81255e1bea5fc85e11741baf7a296d033ec81cce05dede922d60924597ea605a",
       "imageSha256": "329750c81a7a958c4fd105b2c80f85dce55ed87df9ddf0ea08084e4428e85f04"
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     "room-contour-close": {
@@ -47,7 +47,7 @@
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       "language": "en",
-      "sourceSha256": "e9ccc3f9aecc3ce4de775233b9e31aedca19c8a474d9839d96a82ebd79d0f272",
+      "sourceSha256": "81255e1bea5fc85e11741baf7a296d033ec81cce05dede922d60924597ea605a",
       "imageSha256": "ff2e903e548423aa0aa52680e20b8ad951c704e01130cb4b180222015a241276"
     },
     "plan-context-tray": {
@@ -58,7 +58,7 @@
       },
       "theme": "dark",
       "language": "en",
-      "sourceSha256": "e9ccc3f9aecc3ce4de775233b9e31aedca19c8a474d9839d96a82ebd79d0f272",
+      "sourceSha256": "81255e1bea5fc85e11741baf7a296d033ec81cce05dede922d60924597ea605a",
       "imageSha256": "ff55925f079411023442e7e7dd5ed528c331aaa3fd3fc2fbbf3b1aaf34a85718"
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     "device-editor": {
@@ -69,7 +69,7 @@
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       "theme": "dark",
       "language": "en",
-      "sourceSha256": "e9ccc3f9aecc3ce4de775233b9e31aedca19c8a474d9839d96a82ebd79d0f272",
+      "sourceSha256": "81255e1bea5fc85e11741baf7a296d033ec81cce05dede922d60924597ea605a",
       "imageSha256": "6b9cd281450e7782cff292f11efc58d227bedd0df86afc3be987feb2edec9dc3"
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     "device-display-preview": {
@@ -80,7 +80,7 @@
       },
       "theme": "dark",
       "language": "en",
-      "sourceSha256": "e9ccc3f9aecc3ce4de775233b9e31aedca19c8a474d9839d96a82ebd79d0f272",
+      "sourceSha256": "81255e1bea5fc85e11741baf7a296d033ec81cce05dede922d60924597ea605a",
       "imageSha256": "6f628abe6b89d7c4b352e6d73ac0b126526f6fdba5927bb774c5b884e484ca19"
     },
     "background-editor": {
@@ -91,7 +91,7 @@
       },
       "theme": "dark",
       "language": "en",
-      "sourceSha256": "e9ccc3f9aecc3ce4de775233b9e31aedca19c8a474d9839d96a82ebd79d0f272",
+      "sourceSha256": "81255e1bea5fc85e11741baf7a296d033ec81cce05dede922d60924597ea605a",
       "imageSha256": "a1d1a905f1410f73231d2ea5d1dfbd8ae79c2fe8b0a79cff87ebb977ac7a3103"
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@@ -102,7 +102,7 @@
       },
       "theme": "dark",
       "language": "en",
-      "sourceSha256": "e9ccc3f9aecc3ce4de775233b9e31aedca19c8a474d9839d96a82ebd79d0f272",
+      "sourceSha256": "81255e1bea5fc85e11741baf7a296d033ec81cce05dede922d60924597ea605a",
       "imageSha256": "48a5685039a5e0de2a28190d857b193c86e2e63606e3c7a8c40fc9d2b190da4e"
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     "device-info": {
@@ -113,7 +113,7 @@
       },
       "theme": "dark",
       "language": "en",
-      "sourceSha256": "e9ccc3f9aecc3ce4de775233b9e31aedca19c8a474d9839d96a82ebd79d0f272",
+      "sourceSha256": "81255e1bea5fc85e11741baf7a296d033ec81cce05dede922d60924597ea605a",
       "imageSha256": "29a342811aaedaebc54ba337792d60cb454a7cf4c3063b210f6c4bafe0a4d87b"
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