chore(docs+tests): reactivate EntriesIsolationIntegrationTest and resolve tenant data isolation issues

- Fixed schema isolation handling in Exposed by switching table creation to JDBC and explicitly setting `search_path` in PostgreSQL.
- Removed redundant `runBlocking` calls, unused variables, and IDE warnings in the test.
- Added `JwtDecoder` mock in `@TestConfiguration` to prevent application context loading errors.
- Verified that writes in one tenant schema are no longer visible in another.

chore(config): add `application-test.yaml` for better test environment setup

- Configured H2 as an in-memory database for tests.
- Disabled Flyway and Consul to avoid unnecessary dependencies during testing.

gradle.properties

@@ -5,7 +5,7 @@ android.nonTransitiveRClass=true
 # Kotlin Configuration
 kotlin.code.style=official
 # Increased Kotlin Daemon Heap for JS Compilation
-kotlin.daemon.jvmargs=-Xmx6g -XX:+UseParallelGC -XX:MaxMetaspaceSize=2g
+kotlin.daemon.jvmargs=-Xmx8g -XX:+UseParallelGC -XX:MaxMetaspaceSize=2g
 kotlin.js.compiler.sourcemaps=false
 
 # Kotlin Compiler Optimizations (Phase 5)
@@ -20,7 +20,7 @@ kotlin.stdlib.default.dependency=true
 
 # Gradle Configuration
 # Increased Gradle Daemon Heap
-org.gradle.jvmargs=-Xmx6g -Dfile.encoding=UTF-8 -Dkotlin.daemon.jvm.options\="-Xmx4g" -XX:+UseParallelGC -XX:MaxMetaspaceSize=2g -XX:+HeapDumpOnOutOfMemoryError -Xshare:off -Djava.awt.headless=true
+org.gradle.jvmargs=-Xmx8g -Dfile.encoding=UTF-8 -Dkotlin.daemon.jvm.options\="-Xmx6g" -XX:+UseParallelGC -XX:MaxMetaspaceSize=2g -XX:+HeapDumpOnOutOfMemoryError -Xshare:off -Djava.awt.headless=true
 org.gradle.workers.max=8
 org.gradle.vfs.watch=true