[tkroes]

Summary

Adds documentation for the TryFunction database-write diagnostics introduced in ALCops/Analyzers#590.

• Adds the PC0040 page for direct writes to persistent records, including the rollback behavior, examples, and deliberate non-reports.
• Adds the opt-in PC0041 page for potential writes, including ruleset enablement and safe-call suppression.
• Adds both rules to the PlatformCop index.

Validation

• Markdown lint passed for both pages and the index.
• The Hugo build was not run locally because Hugo is unavailable; the PR build workflow runs Hugo, HTML/link checks, and Markdown lint.