v0.30

release: v0.30 — proxy auto-rotation + VPN-safe injection + UI polish

Bumps app crate versions (wezterm, wezterm-gui, wezterm-dynamic,
wezterm-mux-server, unterm-profile, unterm-agents) + root wezterm-dynamic
pin + WiX installer to 0.30.0; syncs Cargo.lock.

Features:
- Proxy auto-rotation (endpoint-level, software-agnostic failover): pick a
  pool of nodes; a background monitor health-checks the active one and fails
  over to the fastest reachable node when it dies. GUI pool checkboxes +
  toggle in Web Settings, `unterm-cli proxy rotation`, and the
  `proxy.rotation` MCP method. Live per-node availability/latency probes.
- VPN-safe proxy injection: spawn.rs now TCP-probes each proxy endpoint
  before injecting HTTP_PROXY into a shell; an unreachable proxy injects
  nothing and the terminal stays on a direct connection (a dead proxy can no
  longer silently cut a terminal off from the network).
- Robustness: ProxyNodeConfig gains #[serde(default)] so a proxy.json whose
  nodes lack the transient probe fields no longer fails to parse and silently
  resets the whole proxy config to off; probe fields are skip_serializing so
  proxy.json stays name+url only.
- Settings menu: roomier spacing — blank rows between items, inset group
  dividers, the close button dropped lower with a padded pill. Rendered via
  an explicit row-list so the layout math can't drift.
- macOS 26 (Tahoe) Finder Sync fix: LSUIElement + LSMinimumSystemVersion +
  NSExtensionAttributes so Finder actually surfaces the contextual menu.

Website: adds the v0.30 "What's new" entry (en + zh-CN; other locales fall
back to en), bumps the version chips / TL;DR / download tag to v0.30.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>