Fix top-level CLI help and version flags

[120850853]

Summary

• handle top-level --help / -h before defaulting to the start command
• add top-level --version / -V support using the existing version command
• add a focused smoke script for installed CLI flag behavior

Reproduction

From a clean install of copilot-deck@0.1.5:

npm install --ignore-scripts --no-audit --no-fund copilot-deck@0.1.5
./node_modules/.bin/copilot-deck --help

Actual behavior before this change:

TypeError [ERR_PARSE_ARGS_UNKNOWN_OPTION]: Unknown option '--help'

Root cause: the dispatcher defaults any first argument that starts with - to start, so --help is parsed by the strict start-option parser instead of printing the documented top-level help.

Verification

pnpm install --ignore-scripts --frozen-lockfile
pnpm --filter copilot-deck exec tsc
pnpm smoke:cli-flags
pnpm lint
pnpm build
pnpm --filter copilot-deck pack --pack-destination /tmp/earn-micro-scan

Packed tarball smoke:

npm install --ignore-scripts --no-audit --no-fund /tmp/earn-micro-scan/copilot-deck-0.1.5.tgz
./node_modules/.bin/copilot-deck --help
./node_modules/.bin/copilot-deck --version

Both packed CLI commands exit 0, print to stdout, and leave stderr empty.

Duplicate check

I checked open issues and PRs before submitting:

gh issue list --repo liuneng1994/copilot-deck --state open --limit 30
gh pr list --repo liuneng1994/copilot-deck --state open --limit 30

Both were empty at the time of submission.