test: guard VERSION against package.json drift

[kingrubic]

Summary

• add a regression test that compares the dependency-free VERSION constant to package.json#version
• keep runtime version loading unchanged so --version/--help do not import storage dependencies

Fixes #101.

Tests

• PATH=/Users/vsc_agent/.nvm/versions/node/v22.21.0/bin:/Users/vsc_agent/.local/bin:/opt/homebrew/bin:/opt/homebrew/sbin:/usr/local/bin:/System/Cryptexes/App/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/local/bin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/bin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/appleinternal/bin:/pkg/env/global/bin:/Users/vsc_agent/.openclaw/npm/projects/openclaw-codex-8902d781d4/node_modules/@openclaw/codex/node_modules/@openai/codex-darwin-arm64/vendor/aarch64-apple-darwin/codex-path:/Users/vsc_agent/.openclaw/agents/main/agent/codex-home/tmp/arg0/codex-arg0QBIt9S:/opt/homebrew/Cellar/node/25.5.0/bin:/opt/homebrew/opt/node/bin:/Users/vsc_agent/Library/pnpm:/Users/vsc_agent/.local/bin npm test
• npm run build