docs(voice): add current IVR route matrix evidence

[CapuchaRojo]

Summary

Adds the current implementation-truth IVR route matrix after the latest merged voice routing work.

Documents:

• Main menu route truth
• Press 1 renewal/new-patient behavior
• Press 2 annual Florida/MMU state-card separation
• Press 3 business-hours handoff behavior
• Press 3 after-hours deterministic classifier
• Hidden staff-controlled reschedule lane
• Separate cancellation lane
• Veteran callback branch with owner-approved script

Validation

• npm run build passed
• Focused voice tests passed: 7 suites / 208 tests
• git diff --check passed with line-ending warnings only

Guardrails

• Docs-only change
• No runtime behavior changed
• No payment internals changed
• No Acuity mutation behavior changed
• No Studio UI or launchpad.pptx changes