Add documentation consistency tests

[Areen-09]

Description

This PR adds automated documentation drift guard tests to ensure repository documentation stays synchronized with the registered skills.

Changes

• Added tests/test_registry_docs.py with checks for:
  • Documentation page exists for every registered skill.
  • Skills index stays in sync with the registry.
  • Example script index parity.
  • Agent loops documentation coverage.
• Updated docs/TESTING.md to include tests/test_registry_docs.py in framework tests.

Type of Change (Matches Issue Templates)

• Skill Proposal: New Skill (Contains manifest.yaml, skill.py, and instructions.md)
• Bug Report Fix: Non-breaking change which fixes an execution error or framework bug
• Doc Fix: Documentation Update
• Framework Feature / RFC Updates: Core Framework Update (Changes to base_skill.py, loader.py, etc.)

Checklist (all PRs)

• My code follows the Agent Code of Conduct.
• I have run python -m flake8 ., pytest skills/ (or skillware test), and pytest tests/ locally (or the subset relevant to this change).
• CHANGELOG.md updated under [Unreleased] if this PR changes user-visible behavior.
• examples/README.md is updated if this PR adds, renames, or removes a runnable script under examples/.

New or updated skill (complete only if this PR adds or changes a skill under skills/)

Not applicable. This PR does not add or modify any skills.

Constitution & Safety (if adding or modifying a skill)

Not applicable. This PR does not add or modify any skills.

Related Issues

Closes #183

[rosspeili]

Thanks @Areen-09, this is a solid start on #183. The four hard checks in tests/test_registry_docs.py match what we wanted, and they all pass on current main. Nice work on clear failure messages and the examples-index parity logic.

A few items before merge:

1. CHANGELOG.md, please add an [Unreleased] entry under Tests or Added (user-visible CI guard).
2. docs/usage/agent_loops.md, defi/evm_tx_handler is still missing from the reference matrix (called out in [Feat]: CI doc-drift guards — skill catalog and examples index parity #183). Please add a row (Gemini/Claude examples exist) so the soft check can pass, or document an explicit grandfather/TODO if you intentionally defer it. @Hendobox maybe you can guide @Areen-09 or co-author this pr?
3. docs/TESTING.md, you updated the table row; also add a bullet under § Framework test mentioning tests/test_registry_docs.py (same style as test_skill_issuer.py).
4. PR checklist, check Framework Feature, local flake8 / pytest tests/, and CHANGELOG when updated.
5. Nit: typo shoud → should in the GRANDFATHERED_EXAMPLES comment.

Commits look good overall, once those are in, this should be good to merge. Happy to re-review.