docs: 新增任务看板（AI 的 Jira）并配置 .gitignore

- docs/06-tasks.md：MVP 拆为 22 个任务 / 7 个 Phase，带依赖与验收；
  强制"一次只做一个任务、做完即停"，避免一次生成整个项目
- CLAUDE.md：文档地图加入任务看板，并增加按看板单任务开发的规则
- .gitignore：忽略内容素材 family-album-usa/、Notion 导出 notion_docs/、
  备份 *.bak、构建产物 *.wasm

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

.gitignore

@@ -1,27 +1,39 @@
-# ---> Go
-# If you prefer the allow list template instead of the deny list, see community template:
-# https://github.com/github/gitignore/blob/main/community/Golang/Go.AllowList.gitignore
-#
-# Binaries for programs and plugins
-*.exe
-*.exe~
-*.dll
-*.so
-*.dylib
-
-# Test binary, built with `go test -c`
-*.test
-
-# Output of the go coverage tool, specifically when used with LiteIDE
-*.out
-
-# Dependency directories (remove the comment below to include it)
-# vendor/
-
-# Go workspace file
-go.work
-go.work.sum
-
-# env file
-.env
-
+# ---> Go
+# If you prefer the allow list template instead of the deny list, see community template:
+# https://github.com/github/gitignore/blob/main/community/Golang/Go.AllowList.gitignore
+#
+# Binaries for programs and plugins
+*.exe
+*.exe~
+*.dll
+*.so
+*.dylib
+
+# Test binary, built with `go test -c`
+*.test
+
+# Output of the go coverage tool, specifically when used with LiteIDE
+*.out
+
+# Dependency directories (remove the comment below to include it)
+# vendor/
+
+# Go workspace file
+go.work
+go.work.sum
+
+# env file
+.env
+
+# 内容素材（含大体积音频，不纳入版本库；如需可改用 Git LFS / 对象存储）
+/family-album-usa/
+
+# Notion 原始导出（只读存档，不纳入版本库）
+/notion_docs/
+
+# 数据修正脚本生成的备份
+*.bak
+
+# 前端构建产物
+*.wasm
+