fix(hook): tolerate --hook-json flag from Claude Code harness

[Rome-1]

Summary

• Claude Code now appends --hook-json <data> to hook commands at invocation; both CLIs were rejecting it as an unknown flag
• Hook event data comes via stdin, not this flag, so it's safe to discard
• Node.js: added .allowUnknownOption() to the pretool Commander subcommand
• Python: added context_settings={"allow_extra_args": True, "ignore_unknown_options": True} to hook_app

Test plan

• echo '{"tool_name":"Bash","tool_input":{"command":"ls"}}' | rafter hook pretool --hook-json '{}' — no error, returns allow decision
• python -m rafter_cli hook pretool --hook-json '{}' <<< '{"tool_name":"Bash","tool_input":{"command":"ls"}}' — no error
• Existing hook behavior unchanged (stdin JSON still drives decisions)

🤖 Generated with Claude Code

[Rome-1]

Rebuilt this branch so it's mergeable and the fix actually works.

Why a rebuild: the branch had no merge-base with main (it was rooted on an unrelated vitest v4 upgrade history and bundled a large docs: expand skill documentation commit), which is why GitHub showed it conflicting. I re-applied the fix cleanly on current main — the diff is now just the hook change + tests (125/3 instead of 416/272). The unrelated docs/vitest commits were dropped; if the skill-docs expansion is still wanted, it's better as its own PR.

Fixed a real bug in the Python side: the original change set context_settings on the hook_app group, which does not reach subcommand parsing — python -m rafter_cli hook pretool --hook-json '{}' still errored with "No such option: --hook-json" (verified). Moved it to the @hook_app.command(...) decorators for pretool and posttool, where it takes effect.

Also:

• Node needed .allowExcessArguments() in addition to .allowUnknownOption() — the <data> value after --hook-json lands as an excess positional, which Commander rejects on its own.
• Applied to both pretool and posttool (Python's app-level intent covered both; the original Node change only did pretool).
• Added Node + Python regression tests: --hook-json tolerated on both subcommands, --format still honored (not swallowed), no-flag behavior unchanged. CLI_SPEC.md documents the tolerance.

Verified the original repro end-to-end in both languages (exit 0, correct decision). All hook suites green (Node 110, Python 76).