Add documentation header analysis identifying 62 problematic headers

[Copilot]

Summary

Analyzed 874 markdown files (10,020 sections) to identify headers that don't accurately describe their content. Delivers comprehensive reports and tooling for systematic remediation.

Analysis Results

62 problematic headers identified:

• 29 "What is X?" headers that don't answer their question (HIGH) - 93.5% failure rate
• 33 generic headers ("Description", "Overview") obscuring specific content (MEDIUM)

Example from docs/cloud/features/04_infrastructure/warehouses.md:20:

## What is compute-compute separation?

Compute-compute separation is available for Scale and Enterprise tiers.

Header asks a definition question but opens with availability info instead of answering.

Deliverables

Reports:

• HEADER_ANALYSIS_REPORT.md - Full analysis with categorized issues and fix recommendations
• problematic_headers.csv - Sortable spreadsheet (Priority, File, Line, Current/Suggested Headers)
• HEADER_FIX_GUIDE.md - Fix patterns with before/after examples
• HEADER_ANALYSIS_START_HERE.md - Quick reference for different user roles

Reusable Analysis Scripts:

• Header parsing and pattern detection across all markdown files
• "What is X?" specific analysis with opening content evaluation
• CSV generation for issue tracking integration
• Scripts can be re-run as documentation evolves

All intermediate JSON files (10MB+) are gitignored but regenerable via scripts.

Checklist

• Delete items not relevant to your PR

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Project	Deployment	Actions	Updated (UTC)
clickhouse-docs	Ready	Preview	Feb 11, 2026 6:29pm

2 Skipped Deployments

Project	Deployment	Actions	Updated (UTC)
clickhouse-docs-ru	Ignored	Preview	Feb 11, 2026 6:29pm
clickhouse-docs-zh	Ignored	Preview	Feb 11, 2026 6:29pm

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