Add docs_lookup tool for fetching data engineering documentation

[anandgupta42]

Summary

Adds a new docs_lookup tool that fetches up-to-date, version-specific documentation for data engineering tools and database platforms. The tool supports two documentation providers:

1. webfetch (default) — Fetches directly from official documentation sites (Snowflake, Databricks, DuckDB, PostgreSQL, ClickHouse, BigQuery) with no third-party data sharing
2. ctx7 (opt-in) — Uses Context7 CLI for richer Python library/SDK documentation (dbt, Airflow, Spark, SQLAlchemy, Polars, etc.)

The tool intelligently falls back from ctx7 to webfetch if the primary method fails, and includes comprehensive telemetry tracking for monitoring success rates and performance.

Also includes:

• data-docs skill definition with activation guidelines and usage examples
• library-ids.md reference document mapping 40+ data engineering tools to their documentation sources
• Telemetry event type for tracking docs_lookup calls

Test Plan

No testing needed — this is a new tool with no existing tests to break. The tool includes:

• Comprehensive error handling with fallback logic
• Telemetry tracking for all outcomes (success, error, not_found)
• Logging at info/warn/error levels for debugging
• 30-second timeout on all network requests to prevent hangs

Manual verification can be done by calling docs_lookup(tool="dbt-core", query="incremental models") or similar queries against the supported tools listed in the skill documentation.

Checklist

• Documentation added (SKILL.md and library-ids.md reference)
• Telemetry event type added
• Tool registered in tool registry