refactor: migrate to YAML config and add Maven dev/prod profiles

- Replace application.properties with application.yaml (base/prod config)
  and application-dev.yaml (dev overrides: show-sql=true)
- Add Maven 'dev' profile (activeByDefault) and 'prod' profile to pom.xml;
  spring-boot:run picks up the active Spring profile automatically
- Guard DataInitializer.initData with @Profile("dev") so test data is
  never seeded in production

Local dev: ./mvnw spring-boot:run (dev profile active by default)
Production: SPRING_PROFILES_ACTIVE env var controls the Spring profile;
            Maven profiles are irrelevant for the packaged JAR.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/pom.xml

@@ -148,11 +148,34 @@
 	</dependencies>
 
 
+	<profiles>
+		<profile>
+			<id>dev</id>
+			<activation>
+				<activeByDefault>true</activeByDefault>
+			</activation>
+			<properties>
+				<spring.profiles.active>dev</spring.profiles.active>
+			</properties>
+		</profile>
+		<profile>
+			<id>prod</id>
+			<properties>
+				<spring.profiles.active></spring.profiles.active>
+			</properties>
+		</profile>
+	</profiles>
+
 	<build>
 		<plugins>
 			<plugin>
 				<groupId>org.springframework.boot</groupId>
 				<artifactId>spring-boot-maven-plugin</artifactId>
+				<configuration>
+					<profiles>
+						<profile>${spring.profiles.active}</profile>
+					</profiles>
+				</configuration>
 			</plugin>
 		</plugins>
 	</build>

backend/src/main/java/org/raddatz/familienarchiv/config/DataInitializer.java

@@ -16,6 +16,7 @@ import org.springframework.beans.factory.annotation.Value;
 import org.springframework.boot.CommandLineRunner;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Profile;
 import org.springframework.security.crypto.password.PasswordEncoder;
 
 import java.time.LocalDate;
@@ -67,6 +68,7 @@ public class DataInitializer {
     }
 
     @Bean
+    @Profile("dev")
     public CommandLineRunner initData(PersonRepository personRepo,
             DocumentRepository docRepo,
             UserGroupRepository groupRepo) {

backend/src/main/resources/application-dev.yaml

@@ -0,0 +1,3 @@
+spring:
+  jpa:
+    show-sql: true

backend/src/main/resources/application.properties

@@ -1,28 +0,0 @@
-spring.application.name=Familienarchiv
-# --- Datenbank Konfiguration ---
-spring.datasource.url=${SPRING_DATASOURCE_URL}
-spring.datasource.username=${SPRING_DATASOURCE_USERNAME}
-spring.datasource.password=${SPRING_DATASOURCE_PASSWORD}
-spring.datasource.driver-class-name=org.postgresql.Driver
-
-# JPA / Hibernate
-spring.jpa.hibernate.ddl-auto=none
-spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.PostgreSQLDialect
-spring.jpa.show-sql=false
-# --- MinIO (S3) Konfiguration ---
-# Eigene Properties (werden wir in einer Config-Klasse auslesen)
-app.s3.endpoint=${S3_ENDPOINT}
-app.s3.access-key=${S3_ACCESS_KEY}
-app.s3.secret-key=${S3_SECRET_KEY}
-app.s3.bucket=${S3_BUCKET_NAME}
-app.s3.region=${S3_REGION}
-
-# Upload Limits erhöhen (für große Scans)
-spring.servlet.multipart.max-file-size=50MB
-spring.servlet.multipart.max-request-size=50MB
-# --- Excel Import Mapping ---
-# Spaltenindex (0 = Spalte A, 1 = Spalte B, usw.)
-app.import.excel.col.filename=0
-app.import.excel.col.date=1
-app.import.excel.col.location=2
-app.import.excel.col.transcription=3

backend/src/main/resources/application.yaml

@@ -0,0 +1,42 @@
+spring:
+  application:
+    name: Familienarchiv
+
+  datasource:
+    url: ${SPRING_DATASOURCE_URL}
+    username: ${SPRING_DATASOURCE_USERNAME}
+    password: ${SPRING_DATASOURCE_PASSWORD}
+    driver-class-name: org.postgresql.Driver
+
+  jpa:
+    hibernate:
+      ddl-auto: none
+    properties:
+      hibernate:
+        dialect: org.hibernate.dialect.PostgreSQLDialect
+    show-sql: false
+
+  servlet:
+    multipart:
+      max-file-size: 50MB
+      max-request-size: 50MB
+
+app:
+  s3:
+    endpoint: ${S3_ENDPOINT}
+    access-key: ${S3_ACCESS_KEY}
+    secret-key: ${S3_SECRET_KEY}
+    bucket: ${S3_BUCKET_NAME}
+    region: ${S3_REGION}
+
+  admin:
+    username: ${APP_ADMIN_USERNAME:admin}
+    password: ${APP_ADMIN_PASSWORD:admin123}
+
+  import:
+    excel:
+      col:
+        filename: 0
+        date: 1
+        location: 2
+        transcription: 3