feat(goose): complete v1.49 phase3 closeout gates and context fusion plan

Expand Goose v1.49 smoke coverage (memory chat, portal resume, page e2e,
multiturn provider), add canary memory policy lock, refresh baselines, and
ignore one-off evidence artifacts. Document headroom-based context runtime
fusion plan; include auth, scheduled-task, and wechat intent fixes on branch.

Co-authored-by: Cursor <cursoragent@cursor.com>

docs/baselines/README.md

@@ -12,3 +12,5 @@
 | `goose-v149-message-sanitize-latest.json` | `node scripts/compare-goose-v149-message-sanitize.mjs` |
 
 Phase 3 收口：[goose-v149-phase3-closeout.md](../goose-v149-phase3-closeout.md) · 聚合：`node scripts/run-goosed-v149-phase3.mjs`
+
+**Git 策略**：只跟踪语义基线（`*-latest.json`、`*-current.json`、`runtime-baseline-*.json`）。每次 smoke 生成的时间戳 `*-evidence-*.json` 已写入根目录 `.gitignore`，勿提交。