feat(boot-start): support system level register

[gaojunran]

No description provided.

[greptile-apps]

Greptile Summary

This PR upgrades auto-launcher to 1.0.0 and adds system-level (root) boot registration alongside the existing user-level path. The dual-launcher design (current / other) resolves all previously-flagged compile issues (missing MacOSLaunchMode/LinuxLaunchMode imports, missing #[cfg] guards, Clone on AutoLaunch), the disable() swallowing-errors bug, the status false-positive, and the enable() early-return bypassing the cross-level conflict check.

Confidence Score: 4/5

Safe to merge; all prior P0/P1 issues are addressed. Two P2 UX/robustness concerns remain around partial-disable and missing guidance in the dual-enabled status message.

All previously-flagged blocking compile errors and logic bugs are resolved. The two remaining findings are P2: a partial-disable edge case that requires both levels to be simultaneously registered (prevented by the new enable() guard going forward) and a minor status message UX gap.

src/boot_manager.rs (disable() partial-state on cross-level permission failure); src/cli/boot.rs (both-levels status branch)

Important Files Changed

Filename	Overview
src/boot_manager.rs	Core change: dual-launcher design (current + other) with platform-guarded nix UID checks, cross-level conflict guard in enable(), and cross-level cleanup in disable(). Previous compile/import issues are addressed; partial-disable edge case remains.
src/cli/boot.rs	BootEnable now uses is_current_level_enabled(), BootStatus uses a 4-way match on (current, other) — both previously-flagged issues addressed. BootDisable still uses is_enabled() (correct intent) but partial-disable on error is an inherited edge case.
Cargo.toml	auto-launcher bumped from 0.6.0 → 1.0.0; nix added as Unix-only dependency. Straightforward version bump.
docs/guides/boot-start.md	Documentation updated with user-level vs system-level table, sudo examples, and supervisor.user config guidance. No issues.

_{Reviews (5): Last reviewed commit: "fix: misc" | Re-trigger Greptile}

[gaojunran]

P2-1: disable() partial state
Removes current before other. If other then fails (permission denied), current is already gone — half-cleaned with no
indication.

P2-2: (true, true) status branch
Reports both levels enabled but gives no remediation hint, unlike the (false, true) branch.

Both findings assume a both-levels-registered (user / system) state can exist. It cannot — system-level was never supported before this PR, and this PR avoids this case,
so no legacy state exists and enable() prevents it going forward. These finding are wrong.

@jdx ready for a review!