Enhancement: Migrate Room annotation processing from KAPT to KSP

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Summary

The project uses kotlin-kapt to process Room's annotation processor (androidx.room:room-compiler). KSP (Kotlin Symbol Processing) is the modern replacement for KAPT and is now the recommended processor for Room.

Motivation

• KSP is ~2x faster than KAPT because it runs natively in Kotlin, avoiding the Java stub generation step.
• kotlin-kapt is in maintenance mode; JetBrains recommends moving to KSP.
• Room has first-class KSP support since Room 2.5.0 (current version is 2.6.1).
• The app/build.gradle.kts already uses kotlin-kapt and has kapt { correctErrorTypes = true } which can be removed.

Proposed Changes

1. In app/build.gradle.kts (and any module using Room), replace:

   id("kotlin-kapt")

   with:

   id("com.google.devtools.ksp")

2. In build.gradle.kts (root), add the KSP plugin to the buildscript classpath.
3. In DependencyHandlerExtensions.kt, change add("kapt", Dependencies.roomCompiler) to add("ksp", Dependencies.roomCompiler).
4. Update Dependencies.kt: room-compiler artifact stays the same; only the configuration changes.
5. Remove the kapt { correctErrorTypes = true } block from app/build.gradle.kts.
6. Add ksp version constant to Versions.kt (match the Kotlin version).

References

• KSP Quick Start
• Room KSP Support