feat(db): retry on document conflicts

services/database/ProductionDatabaseStrategy.ts

@@ -187,18 +187,46 @@ export class ProductionDatabaseStrategy implements DatabaseStrategy {
 
   private async putDoc<T extends CouchDBDocument>(
     dbName: string,
-    doc: T
+    doc: T,
+    retries = 2
   ): Promise<T> {
-    const response = await this.makeRequest<{ id: string; rev: string }>(
-      'PUT',
-      `/${dbName}/${doc._id}`,
-      doc
-    );
+    try {
+      const response = await this.makeRequest<{ id: string; rev: string }>(
+        'PUT',
+        `/${dbName}/${doc._id}`,
+        doc
+      );
 
-    return {
-      ...doc,
-      _rev: response.rev,
-    };
+      return {
+        ...doc,
+        _rev: response.rev,
+      };
+    } catch (error) {
+      if (
+        error instanceof DatabaseError &&
+        error.status === 409 &&
+        retries > 0 &&
+        doc._rev
+      ) {
+        logger.db.warn('Document conflict detected, retrying update', {
+          dbName,
+          id: doc._id,
+          retriesRemaining: retries,
+        });
+
+        const latest = await this.getDoc<T>(dbName, doc._id);
+        if (latest) {
+          const mergedDoc = {
+            ...latest,
+            ...doc,
+            _rev: latest._rev,
+          };
+          return this.putDoc(dbName, mergedDoc, retries - 1);
+        }
+      }
+
+      throw error;
+    }
   }
 
   private async deleteDoc(