Lohnt sich dein eigenes 100 Questions?

Build me a local AI visibility benchmark for one brand. Requirements:

- Use Node 22, TypeScript, official provider SDKs, SQLite, and a CLI.
- `benchmark --domain example.com --description "..."` creates one immutable run.
- Generate 25 buyer questions from the domain and description, or accept a JSON question file.
- Ask the exact same questions through OpenAI, Anthropic, Gemini, and xAI.
- Use each provider's supported web-search or grounding tool; keys live only in `.env`.
- Limit concurrency per provider, retry transient failures, and preserve failed cells in the report.
- Store prompts, raw answers, citations, timestamps, model ids, and errors in SQLite.
- Detect exact and case-insensitive brand mentions; allow aliases in a config file.
- Extract named competitors with one structured LLM pass after all answers are stored.
- Normalize citation URLs by hostname, canonical URL, and stripped tracking parameters.
- Compute visibility by provider, answer coverage, owned-domain citation rate, and top sources.
- Show missed questions where competitors appear but the target brand does not.
- Render a self-contained static HTML report with filters and expandable raw evidence.
- Export questions, answer metrics, competitors, and citations as CSV files.
- Every aggregate metric must link back to the answer rows used to calculate it.
- Out of scope: accounts, billing, teams, scheduled monitoring, and recommendation generation.
- Include fixture-based tests for mention detection, URL normalization, and metric calculations.
- README: setup, provider-specific grounding caveats, estimated API cost, and exact run commands.