fix: audit completions.js for missing commands and flags

[sametcelikbicak]

Summary

The shell completion scripts in src/commands/completions.js are missing several commands and flags that exist in bin/rolecraft.js.

Location

src/commands/completions.js:1-297

Missing items

Commands: check is missing from the COMMANDS array and from bash/zsh/fish completion scripts.

Flags: --no-mcp and --skills-sh are missing from OPTION_FLAGS.

Expected behavior

1. Add 'check' to the COMMANDS array (line 2-5)
2. Add '--no-mcp', '--skills-sh' to OPTION_FLAGS (line 25-28)
3. Add check to the bash case statement (line 52) and zsh/fish completion handlers

Test hint

Update src/commands/completions.test.js to verify the generated bash/zsh/fish scripts contain the new commands and flags.

[sametcelikbicak]

This issue needs updating: the new --list and --skill flags added to rolecraft install (PR #145) are also missing from completions. These should be added to OPTION_FLAGS along with the original list.