Remove reference to file that no longer exists

[mrubens]

Important

Remove outdated section from .roo/rules/rules.md referencing non-existent file.

• Documentation:
  • Removed outdated section "Adding a New Setting" from .roo/rules/rules.md that referenced a non-existent docs/settings.md file.

^{This description was created by for fd7d241. You can customize this summary. It will automatically update as commits are pushed.}

[delve-auditor]

✅ No security or compliance issues detected. Reviewed everything up to fd7d241.

Security Overview

• 🔎 Scanned files: 1 changed file(s)

Detected Code Changes

Change Type	Relevant files
Refactor	► rules.md     Remove outdated reference to settings.md documentation

Reply to this PR with @delve-auditor followed by a description of what change you want and we'll auto-submit a change to this PR to implement it.