Introduce DmfsTaskFieldHandler and DmfsTaskPropertytHandler + three first handlers

[sunkup]

• Introduce DmfsTaskFieldHandler and DmfsTaskPropertytHandler
• Extract task title and UID field handlers
• extract alarms property handler

[Copilot]

Pull request overview

This PR refactors DmfsTaskProcessor by introducing two handler interfaces (DmfsTaskFieldHandler for main task row fields and DmfsTaskPropertyHandler for property sub-rows) and extracting the first three handlers (UID, Title, Alarms) into separate classes with unit tests. This is a structural refactor to support better separation of concerns and testability of the task mapping logic.

Changes:

• Add DmfsTaskFieldHandler and DmfsTaskPropertyHandler interfaces
• Extract UidHandler, TitleHandler, and AlarmsHandler from inline logic in DmfsTaskProcessor
• Add Robolectric-based unit tests for each new handler

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
lib/src/main/kotlin/at/bitfire/synctools/mapping/tasks/handler/DmfsTaskFieldHandler.kt	New interface for mapping fields from a task row into a Task
lib/src/main/kotlin/at/bitfire/synctools/mapping/tasks/handler/DmfsTaskPropertyHandler.kt	New interface for mapping property sub-rows into a Task
lib/src/main/kotlin/at/bitfire/synctools/mapping/tasks/handler/UidHandler.kt	Extracted UID mapping
lib/src/main/kotlin/at/bitfire/synctools/mapping/tasks/handler/TitleHandler.kt	Extracted title/summary mapping
lib/src/main/kotlin/at/bitfire/synctools/mapping/tasks/handler/AlarmsHandler.kt	Extracted alarm property mapping
lib/src/main/kotlin/at/bitfire/synctools/mapping/tasks/DmfsTaskProcessor.kt	Wires the new handler abstractions and removes inline logic
lib/src/test/kotlin/.../UidHandlerTest.kt	Tests for UidHandler
lib/src/test/kotlin/.../TitleHandlerTest.kt	Tests for TitleHandler
lib/src/test/kotlin/.../AlarmsHandlerTest.kt	Tests for AlarmsHandler