feat: add hook uninstall and alias init

[pixincreate]

Summary

• add first-class hook uninstall support for local and global hook targets
• add key-watch --init <shell> for keywatch and kw aliases without shipping duplicate binaries
• simplify install docs to cargo-first/manual-release flows and update changelog

Verification

• cargo fmt -- --check
• cargo clippy --all-targets --all-features -- -D warnings
• cargo test

[Copilot]

Pull request overview

This PR extends KeyWatch’s CLI to support uninstalling git hooks (local and global via core.hooksPath) and introduces key-watch --init <shell> to provide keywatch/kw aliases without shipping extra binaries, alongside updated distribution docs/changelog.

Changes:

• Added --uninstall-hook and --global support for managing hooks in repo-local .git/hooks or Git’s global hooks directory.
• Added --init bash|zsh|fish|posix to print shell alias initialization for keywatch and kw.
• Removed duplicate wrapper binaries and the install script; updated README + changelog to reflect the new install/uninstall flows.

Reviewed changes

Copilot reviewed 10 out of 10 changed files in this pull request and generated 7 comments.

Show a summary per file

File	Description
src/lib.rs	Implements global/local hook install target resolution, hook uninstall, and shell init output; adds unit tests for hooks-path resolution/safety.
src/cli.rs	Extends CLI options and argument grouping for --uninstall-hook, --global, and --init.
tests/hooks_tests.rs	Updates option construction and adds clap parsing tests for --global/--init interactions.
tests/scanner_tests.rs	Updates option construction to include new CLI fields.
README.md	Updates installation/uninstallation docs; documents global hooks and alias init flow.
CHANGELOG.md	Records the new hook uninstall/global hooks/init changes; notes removal of wrapper binaries/install script.
Cargo.toml	Removes explicit [[bin]] entries for wrapper binaries (relying on default src/main.rs).
src/bin/watch.rs	Removed wrapper binary.
src/bin/keywatch.rs	Removed wrapper binary.
scripts/install.sh	Removed install/uninstall script in favor of documented flows.