feat: OCC and OCS Calendar Import/Export

[SebastianKrupinski]

Summary

This adds the ability to export calendars via the OCS and OCC.

OCC Export

Command: calendar:export
Arguments: userId calendarId format filepath

OCC Import

Command: calendar:import
Arguments: userId calendarId format filepath
Options: errors, validation, supersede, show-created, show-updated, show-skipped, show-errors

OCS Export

Endpoint: /ocs/v2.php/calendar/export
Request: GET/POST
{
"id": "personal",
"fmt": "xcal", (optional "ical, jcal, xcal", defaults to "ical")
"user": "user1" (optional admin permissions required)
}

Performance

• Export performance bottle neck seems to be CPU core max out due to single process execution, tests on dev setup with 16k of events takes about 5min or 60 items / second
• Import performance bottle neck seems to be database write performance, tests on dev setup with 16k of events, takes about 30min or 10 items / second

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Tests (unit, integration, api and/or acceptance) are included
• Screenshots before/after for front-end changes
• Documentation (manuals or wiki) has been updated or is not required
• Backports requested where applicable (ex: critical bugfixes)

[SebastianKrupinski]

Hi @tcitworld

I was wondering if you would be willing to test this out with some of your larger live data calendars?

[kesselb]

Suggested change

	* @template-extends Response<int, array<string, mixed>>
	* @template-extends Response<Http::STATUS_*, array<string, mixed>>

To fix the psalm warning below.

[SebastianKrupinski]

@kesselb you're amazing! You're title should be psalm master!