feat: optimize slot refreshing on timezone change

[SiddheshCodes4554]

PR Description: Optimize Slot Refreshing on Timezone Change

What does this PR do?

This PR optimizes how available slots are refreshed when a booker changes their timezone in the booking interface.

Currently, the application triggers a fresh fetch of available slots from the server whenever the booker's timezone is updated. While this is necessary for events where the schedule is strictly restricted to the booker's timezone (useBookerTimezone: true), it is redundant for standard events where slots can be converted client-side.

Changes:

• Updated useScheduleForEvent to accept the useBookerTimezone configuration.

• Modified the slot fetching logic to conditionally use the booker's timezone in the query key only when useBookerTimezone is enabled.

• Correctly passed the useBookerTimezone flag from BookerWebWrapper and Embed components.

• Fixes Upon changing timezone, we need to update slots when restrictionSchedule is being used with useBookerTimezone enabled #22319

• Fixes CAL-N/A

Visual Demo (For contributors especially)

Image Demo:

A snapshot of a real Cal.com booking page, showing the timezone selector and available slots.

Mandatory Tasks (DO NOT REMOVE)

• I have self-reviewed the code.
• N/A (Documentation update not required for this internal change).
• I confirm automated tests are in place that prove my fix is effective.

How should this be tested?

1. Standard Event (useBookerTimezone: false):
   • Open a booking page.
   • Change your timezone using the selector.
   • Expected: No new getSchedule request in the Network tab. Slots update visually.
2. Restricted Event (useBookerTimezone: true):
   • Open an event where "Restrict schedule to booker timezone" is enabled.
   • Change your timezone.
   • Expected: A new getSchedule request is triggered to recalculate availability server-side.

Checklist

• I have read the contributing guide
• My code follows the style guidelines of this project
• I have checked if my changes generate no new warnings

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