feat(ginit): 新增一键初始化本地 Git 仓库命令

`quicommit ginit`（别名 `gi`）离线完成仓库起步：用 git2 建库并确立初始分支、
写最简 README.md、按根目录标志文件装配 .gitignore、按 --add 添加远程，
`--profile` 可选套用已有 Git 配置。在已有仓库上重复执行只补齐缺失项：绝不覆盖
既有的 README.md/.gitignore、绝不改动已有 remote 的地址、不提供 --force、
不创建首个提交。边界取舍见 ADR 0006，命令命名见 ADR 0005。

实现落在新的 src/git/init.rs（9 个 git 层函数）与 src/commands/ginit.rs，
命令层不直接引用 git2，GitRepo 公开接口未改动，其余命令行为不变。
测试：src/git/init.rs 11 条单元测试、tests/ginit_tests.rs 18 条集成测试；
新增 35 个 ginit_* 消息覆盖 7 种语言。

另将 CONTEXT.md 与 docs/adr/ 纳入版本跟踪（.gitignore 放开 adr/ 与
CONTEXT.md 两条忽略规则）；RAODMAP.md 除 ginit 条目外还包含此前未提交的
规划条目更新。

docs/adr/0001-multi-config-version-resolution.md

@@ -0,0 +1,5 @@
+# Multi-config version resolution for --auto mode
+
+When `--auto` detects the project version, it reads from project config files (e.g. Cargo.toml, package.json). We extended this from 2 formats to 16. 11 formats are structured (JSON, TOML, XML), 5 are code-as-config (Ruby, Scala, Clojure, Elixir, CMake/Meson). We use structured parsers for the first group (adding only `roxmltree` for XML — YAML formats use regex to avoid a new dep) and regex for the second. When multiple config files coexist in the project root, we surface all found versions and let the user pick — rather than imposing a fixed priority order. A `go.mod` file causes an immediate skip to commit-analysis fallback (Go defines versions via git tags, not in go.mod). Only the project root is searched; subdirectories are not recursed.
+
+**Considered Options**: A hardcoded priority list (e.g. Cargo.toml > package.json > …) was rejected because no ordering satisfies every polyglot project. Letting the user choose adds one interaction in the rare multi-config case and avoids surprising wrong picks.