Fix: RangeError - Maximum call stack size exceeded in IonDatetime bindings

[sentry]

This PR addresses the RangeError: Maximum call stack size exceeded occurring due to an infinite synchronous update loop when using IonDatetime with React Hook Form.

Root Cause:
The IonDatetime components in src/pages/(auth)/dob/page.tsx and src/components/ui/form-datetime.tsx were manually wired to React Hook Form. The onIonChange handler would call form.setValue() and form.trigger(), which caused a re-render. The value prop, derived from form.getValues()?.toISOString(), could produce a slightly different string (due to local time vs. UTC date truncation differences or new object reference), causing Ionic to detect a change and re-fire onIonChange immediately. This created an infinite loop, exhausting the call stack within Ionic's internal focus-trapping mechanisms.

Solution:

1. src/pages/(auth)/dob/page.tsx: The IonDatetime component is now wrapped with React Hook Form's <Controller>. This allows for proper management of value and onChange without manual setValue() and trigger() calls.
2. src/components/ui/form-datetime.tsx: The IonDatetime component within FormDateTimeInput also had its onIonChange handler updated to use field.onChange from the FormField render prop.
3. Value Normalization: In both cases, the value passed to IonDatetime is now normalized to a YYYY-MM-DD string (e.g., field.value.toISOString().split('T')[0]). This ensures that Ionic does not detect a spurious change in the value prop due to time/timezone differences or new object references, effectively breaking the infinite loop.

Fixes SH-STUDENT-APP-1S
Fixes TECH-2063

[linear-code]

TECH-2063

[netlify]

✅ Deploy Preview for studenthub-student ready!

Name	Link
🔨 Latest commit	eb3b473
🔍 Latest deploy log	https://app.netlify.com/projects/studenthub-student/deploys/6a5181babbde3a0009c7f16c
😎 Deploy Preview	https://deploy-preview-37--studenthub-student.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify project configuration.

[sentry]

Bug: The date of birth field isn't pre-populated on refresh because form.setValue is called with a string, but the IonDatetime component expects a Date object.
_{Severity: MEDIUM}

Suggested Fix

Convert the date string received from the API into a Date object before calling form.setValue. For example, use new Date(res.candidate_birth_date) when setting the value for the candidate_birth_date field in the useEffect hook.

Prompt for AI Agent

Review the code at the location below. A potential bug has been identified by an AI
agent. Verify if this is a real issue. If it is, propose a fix; if not, explain why it's
not valid.

Location: src/pages/(auth)/dob/page.tsx#L143-L145

Potential issue: On page refresh, when the user profile is not in the Redux store, the
`useEffect` hook fetches the profile and sets the `candidate_birth_date` form value with
a string from the API response. The `IonDatetime` component's `value` is determined by
`field.value instanceof Date`. Since `field.value` is a string, this check fails, the
component's `value` prop becomes `undefined`, and the input field appears empty instead
of showing the user's saved date of birth.

_{Did we get this right? 👍 / 👎 to inform future reviews.}