Complete M16 action select lasso parity

docs/EXECUTION_QUEUE.md

@@ -9,10 +9,10 @@
 | 字段 | 值 |
 | --- | --- |
 | 里程碑 | M16 Main、Mesh、Modifier、Sculpt |
-| 当前任务 | `M16-GAP-00138` |
-| parent manifest | `tests/golden/M16-GAP-00137/manifest.json` |
-| 任务卡 | [`tasks/M16-GAP-00138.md`](tasks/M16-GAP-00138.md) |
-| 专项验收 | `npm --prefix web run test:generated-gap -- --task M16-GAP-00138` |
+| 当前任务 | `M16-GAP-00139` |
+| parent manifest | `tests/golden/M16-GAP-00138/manifest.json` |
+| 任务卡 | [`tasks/M16-GAP-00139.md`](tasks/M16-GAP-00139.md) |
+| 专项验收 | `npm --prefix web run test:generated-gap -- --task M16-GAP-00139` |
 
 领取前执行：
 

docs/status/M16-GAP-00138.md

@@ -0,0 +1,17 @@
+# M16-GAP-00138 Status
+
+status: done
+task: action.select_lasso operator LOCAL_EXACT slice
+updated: 2026-08-20 America/New_York
+
+scope:
+
+- Action Editor lasso selection on `object:WebGapSelectLassoObject`.
+
+evidence:
+
+- Blender desktop and WASM/Main expose matching three location channels with frame 3 selected.
+- Save/reopen is exact; malformed Blend input is rejected without Main mutation.
+- Fixture generation, desktop checker, npm comparator, direct comparator, context handoff and manifest hashing passed.
+
+nextTask: `M16-GAP-00139`

docs/tasks/M16-GAP-00139.md

@@ -0,0 +1,37 @@
+# M16-GAP-00139: operator:action.select_leftright LOCAL_EXACT slice
+
+- task: M16-GAP-00139
+- parent: M16-GAP-00138
+- status: in_progress
+- gap: operator:action.select_leftright
+- ownerFamily: OPERATOR
+- targetImplementationClass: LOCAL_EXACT
+
+## 目标
+
+Make the same minimal fixture produce observable operator:action.select_leftright data in Blender desktop and WASM/Main, with save/reopen stability. Change only this gap; do not expand to other data-blocks, editors, or browsers.
+
+## 输入与范围
+
+- Fixture: `tests/files/web/generated/M16-GAP-00139-operator-action.select_leftright.blend`
+- Generator: `tools/web/generated/M16-GAP-00139.py`
+- Production: `blender-5.2.0/source/blender/web_engine/web_engine_blend_reader.cpp`
+- Checker: `tools/web/check-generated-gap.mjs`
+- Do: field read, desktop/WASM comparison, save/reopen, structured report.
+- Do not: other gaps, Firefox/WebKit, or full editor behavior.
+
+## 验收
+
+build_blender_5.2.0/bin/blender -b --factory-startup --python tools/web/generated/M16-GAP-00139.py -- tests/files/web/generated/M16-GAP-00139-operator-action.select_leftright.blend
+npm --prefix web run test:generated-gap -- --task M16-GAP-00139
+node tools/web/check-generated-gap.mjs --task M16-GAP-00139
+
+Malformed/unsupported, cancellation, duplicate, over-budget, or hash-drift cases must keep in_progress; they must not change Main revision or advance nextTask.
+
+## 交付与回滚
+
+- Reports: `tests/golden/M16-GAP-00139/`
+- Status: `docs/status/M16-GAP-00139.md`
+- Manifest: `tests/golden/M16-GAP-00139/manifest.json`
+- Handoff: `node tools/web/check-task-context.mjs --task M16-GAP-00139 --write`
+- Rollback: remove this task production entry, fixture, tests, reports, manifest, status, and context; restore the parent as queue tail without rewriting parent evidence.