feat: improve skill scores for using-chdb

[popey]

Hullo @auxten 👋

I ran your skill through tessl skill review at work and found some targeted, small, but important improvements. Here's the before/after:

Skill	Before	After	Change
using-chdb	90%	100%	+10%

Changelog category (leave one):

• Improvement

Changelog entry

Improved agent skill description distinctiveness and added validation checkpoints to Session pipeline example.

Documentation entry for user-facing changes

• Documentation is written (mandatory for new features)

Changes summary

Description improvements (92% -> 100%)

• Replaced generic trigger terms ("analyze data", "query files") with chdb-specific triggers ("query files with SQL", "join data across different databases and cloud storage", "run ClickHouse queries in-process", "serverless data pipelines without ETL")
• Added explicit mentions of "chdb" and "DataStore" as trigger terms so the skill activates when users reference the tool by name
• Reduces false-positive activation from generic data analysis requests

Content improvements (88% -> 100%)

• Added verification checkpoints to the Session pipeline example — row count checks after each ingestion step before proceeding to analysis
• Numbered the workflow steps (Step 1: Ingest, Step 2: Verify, Step 3: Analyze) for clearer multi-step guidance

Honest disclosure — I work at @tesslio where we build tooling around skills like these. Not a pitch - just saw room for improvement and wanted to contribute.

Want to self-improve your skills? Just point your agent (Claude Code, Codex, etc.) at this Tessl guide and ask it to optimize your skill. Ping me - @popey - if you hit any snags.

Thanks in advance 🙏

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
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[auxten]

Thank you for your interest in chDB.

To be frank, I don't feel your modifications align with our current expectations for this skill. While it is true that the skill still requires some optimization, we are going to do some big refactor on the skill recently. Maybe you can help us improve it after that.

Regardless, we appreciate your interest.