[AZ-513] [AZ-196] [AZ-183] Add /classes CRUD, /devices, fleet OTA

AZ-513: POST/PATCH/DELETE /classes for detection-class CRUD; new
DetectionClass entity, schema, DTOs, IDetectionClassService. Unblocks
ui/AZ-512.

AZ-196: POST /devices auto-assigns sequential azj-NNNN serial+email
+password and inserts a CompanionPC user. Returns plaintext credentials
for the provisioning script.

AZ-183: Resources table + POST /get-update + POST /resources/publish
for fleet OTA. Per-resource encryption_key column AES-256-CBC encrypted
at rest with ResourcesConfig.EncryptionMasterKey; ICache wraps the
per-(arch,stage) latest-versions lookup and is invalidated on publish.

Adds IDbFactory.RunAdmin<T> overload for write-and-return.

Backfills _docs/02_document/module-layout.md to satisfy the implement
skill's File Ownership prerequisite (the _docs/ artifact set predates
the Step 1.5 module-layout addition).

Code review: PASS_WITH_WARNINGS — see
_docs/03_implementation/reviews/batch_05_review.md.

Co-authored-by: Cursor <cursoragent@cursor.com>

Azaion.Common/Database/AzaionDbShemaHolder.cs

@@ -36,6 +36,17 @@ public static class AzaionDbSchemaHolder
                     p => string.IsNullOrEmpty(p) ? new UserConfig() : JsonConvert.DeserializeObject<UserConfig>(p))
                 .IsNullable();
 
+        builder.Entity<DetectionClass>()
+            .HasTableName("detection_classes")
+            .Property(x => x.Id)
+                .IsPrimaryKey()
+                .IsIdentity();
+
+        builder.Entity<Resource>()
+            .HasTableName("resources")
+            .Property(x => x.Id)
+                .IsPrimaryKey()
+                .HasDataType(DataType.Guid);
 
         builder.Build();
     }