Reconcile package.json metadata with the "Weval" OSS identity

[nojibe]

Problem

package.json metadata doesn't match the project's public open-source identity:

• "name": "llm-sim-suite" — an internal-sounding name, not weval
• No license field (the repo is MIT via LICENSE)
• No description, repository, homepage, or bugs fields
• "private": true

While private: true may be intentional (this is an app, not a published npm package), the missing license/repository/description fields and the legacy name undercut the OSS presentation and tooling (e.g. license scanners, SBOM generators).

Proposed change

• Set "license": "MIT"
• Add description, repository (→ weval-org/app), homepage (→ https://weval.org), and bugs URLs
• Decide whether to rename "name" to weval (or @weval/app) for consistency; document if llm-sim-suite must stay for historical reasons
• Keep private: true unless publishing is intended

Acceptance criteria

• license field present and matches LICENSE
• repository/homepage/bugs populated
• name decision made and applied/documented