What

• Add API reference pages for pythonnative.events, pythonnative.mutations, and pythonnative.platform_metrics.
• Wire the new pages into the API Reference section of mkdocs.yml.
• De-duplicate embedded blocks in docs/api/native_views.md in favor of dedicated pages.

Why

• These modules had docstrings ready for mkdocstrings but were missing standalone pages in the API reference.

How (brief)

• Created docs/api/events.md, docs/api/mutations.md, and docs/api/platform_metrics.md with module intros, mkdocstrings directives (filters: ["!^_"]), and "Next steps" cross-links.
• Updated mkdocs.yml navigation to include the three new pages.
• Verified that mkdocs build --strict builds cleanly with zero warnings or broken references.

Testing

• Ran mkdocs build --strict locally; site builds cleanly in strict mode.

Risks/Impact

• Low risk; documentation only.

Docs/Follow-ups

• None required.

Closes #24