feat(docs): Adding information about parameter c= (#26430)

* Adding information about parameter c=

* Apply suggestions from code review

Co-authored-by: bo0tzz <git@bo0tzz.me>

---------

Co-authored-by: Jason Rasmussen <jason@rasm.me>
Co-authored-by: bo0tzz <git@bo0tzz.me>

mobile/openapi/lib/model/asset_response_dto.dart

@@ -156,7 +156,7 @@ class AssetResponseDto {
 
   List<TagResponseDto> tags;
 
-  /// Thumbhash for thumbnail generation
+  /// Thumbhash for thumbnail generation (base64) also used as the c query param for thumbnail cache busting.
   String? thumbhash;
 
   /// Asset type

open-api/immich-openapi-specs.json

@@ -17070,7 +17070,7 @@
             "type": "array"
           },
           "thumbhash": {
-            "description": "Thumbhash for thumbnail generation",
+            "description": "Thumbhash for thumbnail generation (base64) also used as the c query param for thumbnail cache busting.",
             "nullable": true,
             "type": "string"
           },

open-api/typescript-sdk/src/fetch-client.ts

@@ -616,7 +616,7 @@ export type AssetResponseDto = {
     resized?: boolean;
     stack?: (AssetStackResponseDto) | null;
     tags?: TagResponseDto[];
-    /** Thumbhash for thumbnail generation */
+    /** Thumbhash for thumbnail generation (base64) also used as the c query param for thumbnail cache busting. */
     thumbhash: string | null;
     /** Asset type */
     "type": AssetTypeEnum;

server/src/dtos/asset-response.dto.ts

@@ -25,7 +25,10 @@ export class SanitizedAssetResponseDto {
   id!: string;
   @ValidateEnum({ enum: AssetType, name: 'AssetTypeEnum', description: 'Asset type' })
   type!: AssetType;
-  @ApiProperty({ description: 'Thumbhash for thumbnail generation' })
+  @ApiProperty({
+    description:
+      'Thumbhash for thumbnail generation (base64) also used as the c query param for thumbnail cache busting.',
+  })
   thumbhash!: string | null;
   @ApiPropertyOptional({ description: 'Original MIME type' })
   originalMimeType?: string;