feat: Domain-wide delegation for Google Calendar and Google Meet

[hariombalhara]

What does this PR do?

Demo - https://www.loom.com/share/1f9e7c79697847a8bb37490e9873fb26

For feature details refer to README

Detailed Changes

• getCalendar now requires value of type CredentialForCalendarService which needs an explicit value for delegatedTo. It makes it clear to CalendarService how that Credential should be used.
  • For regular credentials,delegatedTo=null.
  • For DWD credentials, delegatedTo={ serviceAccountKey: { client_email: string; private_key: string; client_id: string;}}
• google-calendar/CalendarService now supports impersonating a user using the ServiceAccount and thus is capable of taking actions on any of the organization member's behalf on the Google Calendar.

Calendar Cache support is part of #18619

Release Plan

1. Read the document(domain-wide-delegation.md) and acknowledge it.
2. Deploy:
   1. Follow "Setting up Domain-Wide Delegation for Google Calendar API" in domain-wide-delegation.md to create Service Account and create a workspace.
   2. Merge PR(without Calendar Cache Support) and then deploy.
3. Enable for i.cal.com:
   1. Disable Calendar Cache for i.cal.com
   2. Enable teamFeature "domain-wide-delegation" for i.cal.com organization
   3. Create DWD for i.cal.com first and enable it.
   4. Wait for 1-2 days and keep monitoring the errors in Sentry and Axiom.
4. Merge & Deploy the Calendar Cache support(with DWD) PR
   1. Enable Calendar Cache back for i.cal.com
   2. Observe the errors in Sentry and Axiom.
5. Enable for a big customer:
   1. Wait for a week and keep monitoring the errors in Sentry and Axiom.
6. Use delegatedCredentialsFirst instead of delegatedCredentialsLast in EventManager.ts
   - Observe errors in Sentry and Axiom.

Automated Tests

• Slots Availability - getSchedule.test.ts

• Google Calendar Service - Calendar.test.ts

• DomainWideDelegation utiltiies and repository - server.test.ts and domainWideDelegation.test.ts

• Updating/Setting destinationCalendar - setDestinationCalendar.handler.test.ts

• Doing a booking - domain-wide-delegation.test.ts

• Fixes CAL-4610

Possible errors when enabling DWD

Mandatory Tasks (DO NOT REMOVE)

• I have self-reviewed the code (A decent size PR without self-review might be rejected).
• N/A I have added a Docs issue here if this PR makes changes that would require a documentation change. If N/A, write N/A here and check the checkbox.
• I confirm automated tests are in place that prove my fix is effective or that my feature works.

How should this be tested?

• Test different scenarios like rescheduling, reassignment, team bookings etc.
• Refer to https://github.com/calcom/cal.com/blob/domain-wide-delegation-google-calendar/apps/web/app/settings/(settings-layout)/organizations/domain-wide-delegation/domain-wide-delegation-TODO.md to see what has been tested

[github-actions]

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Name	Status	Preview	Comments	Updated (UTC)
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[github-actions]

E2E results are ready!

• Workflow #47681.1 latest results