feat(init): record init URL (#18)

feat(skills): add --force/-f to `skills install` to reinstall install…

…ed skills (#17)

`clime skills install <repo>` filters out already-installed skills from
the selection picker, so there is no way to reinstall/refresh a skill you
already have (short of `uninstall` then `install`). The interactive
"Update installed skills" action exists but isn't reachable from the
`install <repo>` command directly.

Add `--force`/`-f`: when installing from a repo, already-installed skills
are kept in the picker (marked `(reinstall)`) instead of being filtered
out, and reinstalling overwrites their files. Non-force behavior and the
interactive source menu are unchanged.

The candidate-filtering logic is extracted into a pure
`selectInstallCandidates` helper and unit-tested for both default and
force modes.

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

Normalize bare owner/repo npm sources and detect installed bin

Fixes a confusing failure when users pass --npm owner/repo: npm treats it
as a GitHub shorthand instead of a scoped package, so no binary is
created and the install fails with "binary not found". NewNpmInstaller
now rewrites bare owner/repo strings to @owner/repo, and Install snapshots
the npm global bin dir to discover binaries with unexpected names and
report a helpful error when none are produced.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Reinstall script plugins on init when the install URL changes (#15)

Add the auth instruction for skills

Update the source repo before installing skills

Allow using the interactive UI to install plugins

Warning if removes a non-exists plugin

Only download the missing plugins in command

Change the skill subcommand to install skill subcommand for CLI