bug: Ad-hoc mentor availability collected as number of mentees but submitted as hours

[yingliu-data]

Bug Report

Ad-hoc mentor availability is collected in the UI as "number of mentees" but submitted to the backend as "hours", so the stored/displayed semantics are wrong.

• src/components/mentorship/Step1BasicInfo.tsx:255-260 — the radio grid is labelled "maximum number of mentees you are available to support" (values 1-5).
• src/pages/api/mentor-registration.ts:36-66 (esp. line 63) maps that value into hours: parseInt(availability).
• Backend MentorMonthAvailability(Month month, Integer hours) stores it as hours.

Additionally, long-term hours is silently fabricated as numMentee * 2 (lines 8-9, 29-34) rather than collected.

Reproduction

A mentor selects "5 mentees in May" → stored and later displayed as "5 hours in May". Capacity planning and AD_HOC cycle filtering then operate on incorrect semantics.

Severity

Medium

Potential Risk

• Corrupted availability/capacity data feeding matching and cycle filtering.

Suggested Fix

• Align the field: either collect actual hours in the UI, or add/route a distinct "number of mentees" field to the correct backend field, and stop conflating the two.
• Stop fabricating long-term hours from numMentee; collect it explicitly or send the value the backend actually expects.
• Add a test asserting the submitted payload matches the UI's meaning.