feat(cli): add qawolf help ref for a command subtree's help

[Erzhan Torokulov (erzhtor)]

Relates to AGE-5384.

Overview of Changes

Agents learn the runner commands from three hand-written copies: each command's --help, references/runner.md, and the platform's own Tester skill. They drift, and only --help is versioned with the binary an agent actually runs. This stack makes the CLI's help the one source.

This PR adds the read side. qawolf help ref [command...] (alias reference) prints the full --help of a command and of every visible command under it as Markdown: one heading per command, nested by depth, each followed by its help in a text block. qawolf help ref runner is every runner command in one read instead of 29.

• Commander's built-in help [command] can't take a subcommand of its own, so program.ts turns it off and help/index.ts registers a replacement. qawolf help <command> behaves as before; an unknown path exits 2.
• The help is captured through outputHelp(), not helpInformation(), because the latter drops addHelpText (every Examples block). It wraps at a fixed 100 columns so the output doesn't depend on the terminal.
• The tree walk is shared with the generated command table in skill.ts.

Stack:

#	PR	Contribution
1	#1651 (this PR)	qawolf help ref [command...] prints a command subtree's full help as Markdown
2	#1652	runner.md's knowledge moves into each runner command's --help; runner.md is generated from qawolf help ref runner
3	qawolf/platform#34845	Tester's qawolf-cli skill points at the CLI's help instead of restating it

#1652 is stacked on this PR, and both ship together in 1.40.0. qawolf/platform#34845 waits for that release.

Testing

bun run typecheck && bun run lint && bun run format:check && bun run knip && bun run test && bun run build

New tests cover nested headings, hidden commands, addHelpText text, the reference alias, help <command>, and unknown paths. A snapshot pins help ref runner. Only the root --help snapshot changed (the help row). All tests pass except 3 keychain tests that also fail on main on this machine.

Checklist

• Changes follow the code style of this project
• Self-review completed
• Tests added/updated (or not applicable)
• No breaking changes (or described below)