fix(tests): resolve EntriesIsolationIntegrationTest failures with test-specific DB config

- Added `TestExposedConfiguration` to connect Exposed with Spring `DataSource` in the `test` profile.
- Downgraded `springdoc` version from `3.0.0` to `2.8.9` for Spring Boot 3.x compatibility.
- Applied `@ActiveProfiles("test")` to `EntriesIsolationIntegrationTest`.
- Updated roadmap documentation to reflect bugfix and test success.

Signed-off-by: Stefan Mogeritsch <stefan.mo.co@gmail.com>

backend/services/entries/entries-service/src/test/kotlin/at/mocode/entries/service/config/TestExposedConfiguration.kt

@@ -0,0 +1,21 @@
+package at.mocode.entries.service.config
+
+import org.jetbrains.exposed.v1.jdbc.Database
+import org.springframework.context.annotation.Bean
+import org.springframework.context.annotation.Configuration
+import org.springframework.context.annotation.Profile
+import javax.sql.DataSource
+
+/**
+ * Verbindet Exposed mit der Spring-DataSource im Test-Profil.
+ * Ersetzt die EntriesDatabaseConfiguration (die mit @Profile("!test") ausgeschlossen ist).
+ */
+@Configuration
+@Profile("test")
+class TestExposedConfiguration {
+
+  @Bean
+  fun exposedDatabase(dataSource: DataSource): Database {
+    return Database.connect(dataSource)
+  }
+}

backend/services/entries/entries-service/src/test/kotlin/at/mocode/entries/service/tenant/EntriesIsolationIntegrationTest.kt

@@ -18,6 +18,7 @@ import org.junit.jupiter.api.extension.ExtendWith
 import org.springframework.beans.factory.annotation.Autowired
 import org.springframework.boot.test.context.SpringBootTest
 import org.springframework.jdbc.core.JdbcTemplate
+import org.springframework.test.context.ActiveProfiles
 import org.springframework.test.context.DynamicPropertyRegistry
 import org.springframework.test.context.DynamicPropertySource
 import org.springframework.test.context.TestPropertySource
@@ -52,6 +53,7 @@ import kotlin.uuid.Uuid
   // Als Fallback: Bean-Override in Testkontext erlauben (sollte i.d.R. nicht nötig sein)
   "spring.main.allow-bean-definition-overriding=true"
 ])
+@ActiveProfiles("test")
 @Testcontainers
 @TestInstance(Lifecycle.PER_CLASS)
 class EntriesIsolationIntegrationTest @Autowired constructor(