feat(ECR-011): 昵称、首页贴士与档案 Self 唯一/合盘交叉校验

每账号仅一条 self（migration 40902）；合盘只选 TA；账号昵称可改；首页穿衣/颜色/养生贴士。

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

docs/TASKS/TASK-011-ECR011.yaml

@@ -0,0 +1,19 @@
+ecr: ECR-011
+title: identity nickname home tips profile integrity
+status: implemented
+owner: reviewer
+change_level: L2
+artifacts:
+  - docs/ECR/ECR-011-identity-home-profile.md
+  - docs/BACKEND_DESIGN/BD-2026-011-identity-home-profile.md
+  - docs/ENGINEERING_SPEC/ECR-011-identity-home-profile.md
+  - docs/PRODUCT_SPEC/ECR-011-identity-home-profile.md
+  - docs/HANDOFF/ECR-011-architect-to-engineer.md
+  - docs/HANDOFF/ECR-011-engineer-to-reviewer.md
+  - docs/HANDOFF/ECR-011-implementation-report.md
+  - docs/TEST_REPORT/ECR-011.md
+  - .ai/product/feature-spec/profile.md
+  - .ai/product/feature-spec/star-profile.md
+  - .ai/product/feature-spec/account-auth.md
+  - .ai/product/feature-spec/home.md
+notes: Implemented 2026-08-12; awaiting Reviewer; integration needs deps:up