Read/write events as EventAndExceptions data object

[rfc2822]

To be merged for bitfireAT/davx5-ose#1605 / DAVx5 4.5.4

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• Introduced EventAndExceptions data object for local storage that contains a main event and optional exceptions for it (not to be confused with an Entity that comprises a main event row and its data rows, or with AssociatedEvents that is in iCalendar level, not on local storage level)
• LegacyAndroidEventBuilder which generated a BatchOperation (operation) rewritten to LegacyAndroidEventBuilder2 that generates a EventAndExceptions object (data object, doesn't contain operations and thus can be tested much easier)
  • test was adapted to new API structure, but the assertions themselves were not changed
• AndroidEvent removed
• AndroidRecurringCalendar provides CRUD for EventAndExceptions

The big goal is that

• every CalDAV calendar storage object (represented as AssociatedEvents) can be mapped to exactly one data object (EventAndExceptions) and vice versa,
• this mapping is done completely separated from storage,
• the mapped object can be read/written on storage level.

[rfc2822]

Basically ready, but I will have another look when DAVx5 4.5.3 is released

[Copilot]

Pull Request Overview

This PR refactors the Android calendar event handling system by introducing the EventAndExceptions data object pattern. The goal is to cleanly separate data mapping from storage operations and ensure one-to-one mapping between CalDAV storage objects and local data objects.

Key changes:

• Introduced EventAndExceptions data object for local storage containing main events and exceptions
• Created LegacyAndroidEventBuilder2 to generate data objects instead of batch operations
• Added AndroidRecurringCalendar for CRUD operations on events with exceptions
• Removed deprecated AndroidEvent class

Reviewed Changes

Copilot reviewed 20 out of 20 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
EventAndExceptions.kt	New data class representing main event and its exceptions
AndroidRecurringCalendar.kt	New class handling CRUD operations for events with exceptions
LegacyAndroidEventBuilder2.kt	Refactored builder to generate data objects instead of batch operations
AndroidCalendar.kt	Enhanced with batch operation support and entity-based methods
Test files	Updated tests to work with new data object pattern

Comments suppressed due to low confidence (1)

lib/src/main/kotlin/at/bitfire/synctools/mapping/calendar/LegacyAndroidEventBuilder2.kt:63

• [nitpick] The class name 'LegacyAndroidEventBuilder2' suggests this is a temporary naming scheme. Consider using a more descriptive name like 'AndroidEventDataBuilder' or 'EventAndExceptionsBuilder' to better reflect its purpose.

class LegacyAndroidEventBuilder2(

[rfc2822]

I understand that this is hard to review … but maybe you see something that looks really strange to you @sunkup

[sunkup]

Yes well, we talked about it twice already and the structural changes are really nice improvement. I don't see any major issues in the code, but there are two small things that I don't understand entirely and would love to hear some clarification on.