[codex] Preserve legacy sync behavior without state

[felipe0328]

Summary

Restores backward-compatible ./sync.sh behavior for machines configured before the v1.2 component-state system existed, including the repository Git-hook refresh performed by the legacy sync command.

Previously, a pre-v1.2 machine had no ~/.config/power_mac/state, so the same no-argument ./sync.sh command that used to refresh configs exited with an error after upgrading to v1.2.

What changed

When sync.sh runs without explicit selection flags, it now follows this order:

1. Use the saved component state when available.
2. If state is missing, detect component configs already symlinked to this repository.
3. If managed symlinks are detected, sync only those components.
4. If nothing can be detected, fall back to the exact legacy config set: Shell, WezTerm, Neovim, and AeroSpace.
5. Reinstall this repository's Git hooks after every successful sync.
6. After hooks succeed, save the detected or fallback selection for future runs.

Tmux is intentionally excluded from the fallback because the pre-v1.2 sync.sh did not manage Tmux configuration.

Safety and compatibility

• Detection is generic and derives ownership from each component's declared config mappings.
• Both absolute and repository-managed symlink targets are matched without changing unrelated files.
• Hook failure makes the sync fail and prevents migrated state from being persisted.
• State is written only after every selected config and the Git-hook setup succeed.
• --dry-run reports config and hook operations without persisting state or invoking the hook installer.
• Explicit --all and --components behavior remains unchanged.

Validation

• bash -n install.sh sync.sh lib/*.sh components/*.sh tmux-installer/tmux-installer.sh tests/installer_test.sh
• shellcheck install.sh sync.sh lib/*.sh components/*.sh tmux-installer/tmux-installer.sh tests/installer_test.sh
• ./tests/installer_test.sh — 22/22 tests passing

Regression coverage verifies detected legacy migration, the exact legacy fallback set, exclusion of Tmux, Git-hook installation, hook-failure state safety, and dry-run non-persistence.

[github-actions]

Version preview

Current	Expected after merge	Bump
1.2.0	1.2.1	patch

This PR will trigger a version bump after it is merged into main.

conventional commits require patch bump.

[chatgpt-codex-connector]

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