fix(session): restore pane cwd when OSC 7 reports the local hostname

[dufu1991]

Problem

Session restore reopens tabs/splits correctly, but every pane lands in $HOME. last_session.json saves each pane's working_dir, but cwd_from_working_dir() converts it with url::Url::to_file_path(), which on unix refuses any host other than empty or localhost (verified against the url crate source: None | Some(Host::Domain("localhost")) => None, _ => return Err(())).

OSC 7 is conventionally reported as file://$HOST$PWD — WezTerm's own shell integration does exactly this — and the snapshot stores the URL verbatim. Verified live on macOS: emitting \033]7;file://<hostname>.local/tmp/x\033\\ into a pane makes kaku cli list report exactly that URL, and every entry in a real last_session.json shows the same shape (file://df-macbook-pro-14.local/Users/...). All of them fail to_file_path() -> cwd_for_restore() returns None -> panes spawn at the default cwd.

The ssh-domain branch of cwd_for_restore() already special-cases this to_file_path() limitation for remote hosts; local panes hit the same wall when the OSC 7 host is the local hostname.

Fix

In cwd_from_working_dir(), treat a file:// URL whose host identifies this machine as local: strip the host before calling to_file_path().

• Accept both the full hostname and its first label (zsh $HOST, hostname, and scutil --get LocalHostName disagree on whether the domain part is included).
• Compare case-insensitively: the URL parser lowercases the host, while macOS hostnames are often mixed case.
• Tolerate a trailing dot (FQDN form).
• Any other host still fails conversion, preserving the existing guarantee that a leftover remote cwd cannot leak into a local spawn.

Tests

• Extended restore_cwd_local_domain_requires_local_url with a localhost case; the remote-host rejection case is unchanged.
• Added restore_cwd_local_domain_accepts_local_hostname: real hostname (uppercased to prove case-insensitivity), short hostname, and trailing-dot FQDN. The hostname is read at runtime, so the test is machine-independent.

Verification

• make fmt-check passes.
• cargo test --locked -p kaku-gui session_restore covers the new and existing restore-cwd tests (cold full-workspace build is slow on the author's machine; the checks workflow covers fmt/check/tests on the PR).

中文摘要

问题：会话恢复后所有 pane 都打开在 $HOME。快照里保存的 working_dir 是带本机真实主机名的 file:// URL（OSC 7 的惯例格式 file://$HOST$PWD），而恢复端 cwd_from_working_dir() 调用的 url::Url::to_file_path() 在 unix 上拒绝任何非空、非 localhost 的 host，导致路径转换失败、pane 以默认目录启动。ssh 分支之前已经针对这个限制做过处理，但本地 pane 在 host 是本机主机名时撞上了同一堵墙。

修复：转换前把"本机主机名"（全名或首段、忽略大小写、容忍 FQDN 尾点）识别为本地并剥离 host；其他 host 依旧拒绝，保留"远程路径不得泄漏进本地 spawn"的防护。附带覆盖本机主机名三种形态的单元测试，并通过 make fmt-check。

[vercel]

@dufu1991 is attempting to deploy a commit to the Faberon Team on Vercel.

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[tw93]

@dufu1991 Thanks for tracking down the OSC 7 restore case and adding the initial coverage. I tightened hostname validation so a same-named host inside a regular SSH session is not treated as local, and the fix is now merged.

It is available in the latest Nightly: https://github.com/tw93/Kaku/releases/download/nightly/Kaku-nightly.dmg