Move Category model and repository to domain and data layer (#8967)

To keep the commit from being 100+ files the interactors wasn't moved.

The domain module like the data module uses `tachiyomi` instead of `eu.kanade.tachiyomi` for package names

domain/build.gradle.kts

@@ -0,0 +1,19 @@
+plugins {
+    id("com.android.library")
+    kotlin("android")
+}
+
+android {
+    namespace = "tachiyomi.domain"
+
+    defaultConfig {
+        testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
+        consumerProguardFiles("consumer-rules.pro")
+    }
+
+}
+
+dependencies {
+    implementation(platform(kotlinx.coroutines.bom))
+    implementation(kotlinx.bundles.coroutines)
+}