feat: add shared runner metadata and centralize runner detection

[Ishita-190]

Fixes: #40

Files changed: language.ts, package.ts, package.spec.ts
In language.ts:

• Runner union
• RunnerInfo interface
• Runners map (file patterns, install commands, display name, language mapping)
• detectRunnersFromFiles(files) helper

In package.ts:

• findRunners now uses shared detection from language metadata

In package.spec.ts:

• Coverage for detectRunnersFromFiles

Checklist:

• npm test
• npm run lint
• npx tsc --noEmit

All tests are working properly:

Note: findRunners now returns Set<Runner> instead of Set<string>. Runtime behavior is unchanged.

I'll have to modify the following files in https://github.com/metacall/faas to move runner logic to protocol:

• package.json– bump protocol dependencies
• src/install.ts – remove duplicated runner definitions and use protocol instead
• src/app.ts – update runner typing from string[] to runner[]
• src/repository.ts – use protocol runner detection
• src/package.ts – validate and parse runners using protocol types