feat: Maven multimodule scaffolding for Ordinis MDM service

- 10 модулей (domain, validation, events-api, outbox, rest-api, app, read-api, projection-writer, cuod-bundle, migrations)
- Parent pom + BOM с Spring Boot 3.4.2, Spring Cloud 2024.0.0, Vault Config 4.2.0
- ordinis-app: Spring Boot main с Actuator/Prometheus/Logstash JSON encoder/OpenTelemetry/Cloud Config/Vault skeleton
- ordinis-migrations: Liquibase changelogs (dictionary_definitions/records, audit_log, outbox_events, idempotency_keys, EXCLUSION CONSTRAINT через btree_gist)
- Multi-stage Dockerfiles для app и migrations

.gitignore

@@ -0,0 +1,23 @@
+target/
+*.class
+*.jar
+*.war
+*.iml
+.idea/
+.vscode/
+.DS_Store
+*.bak
+
+# Maven
+dependency-reduced-pom.xml
+
+# Spring Boot
+*.tmp
+HELP.md
+
+# Logs
+*.log
+
+# Sensitive
+*.pem
+*.key