feat(infra): proto-to-graphql generator + debezium outbox connector

- M0: parse proto to generate Federation 2 subgraph SDL

- M0.5: Debezium Connect monitors 4 outbox tables

- docker-compose: extend Debezium profiles to default+p3+p4+p5+p6

- package.json: add proto:gen-graphql script

infra/debezium/connectors/edu-outbox-connector.json

@@ -0,0 +1,37 @@
+{
+  "name": "edu-outbox-connector",
+  "config": {
+    "connector.class": "io.debezium.connector.mysql.MySqlConnector",
+    "database.hostname": "MYSQL_HOST_PLACEHOLDER",
+    "database.port": "MYSQL_PORT_PLACEHOLDER",
+    "database.user": "MYSQL_USER_PLACEHOLDER",
+    "database.password": "MYSQL_PASSWORD_PLACEHOLDER",
+    "database.server.id": "5400",
+    "database.allowPublicKeyRetrieval": "true",
+    "database.include.list": "next_edu_cloud",
+    "table.include.list": "next_edu_cloud.iam_outbox,next_edu_cloud.core_edu_outbox,next_edu_cloud.content_outbox_events,next_edu_cloud.msg_outbox_events",
+    "database.server.name": "edu-cdc",
+    "topic.prefix": "edu-cdc",
+    "schema.history.internal.kafka.bootstrap.servers": "kafka:29092",
+    "schema.history.internal.kafka.topic": "edu-cdc-schema-history",
+
+    "transforms": "unwrap,topicRouter",
+    "transforms.unwrap.type": "io.debezium.transforms.ExtractNewRecordState",
+    "transforms.unwrap.drop.tombstones": "true",
+    "transforms.unwrap.delete.handling.mode": "rewrite",
+
+    "transforms.topicRouter.type": "org.apache.kafka.connect.transforms.RegexRouter",
+    "transforms.topicRouter.regex": "edu-cdc\\.next_edu_cloud\\.(iam_outbox|core_edu_outbox|content_outbox_events|msg_outbox_events)",
+    "transforms.topicRouter.replacement": "edu.outbox.events",
+
+    "key.converter": "org.apache.kafka.connect.storage.StringConverter",
+    "value.converter": "org.apache.kafka.connect.json.JsonConverter",
+    "value.converter.schemas.enable": "false",
+
+    "snapshot.mode": "schema_only_recovery",
+    "tombstones.on.delete": "false",
+    "poll.interval.ms": "500",
+    "max.batch.size": "2048",
+    "max.queue.size": "8192"
+  }
+}