feat: show file checksum instead of format in full item view

Replace the per-file "Format" line in the full item view file listing
with a "File checksum" line (algorithm + value). Add the checkSum field
to the Bitstream model so the REST value deserializes, and add the
item.page.filesection.checksum i18n key.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: jr-rk

src/app/core/shared/bitstream.model.ts

@@ -32,6 +32,15 @@ export class Bitstream extends DSpaceObject implements ChildHALResource {
   @autoserialize
   sizeBytes: number;
 
+  /**
+   * The checksum of this Bitstream, including the algorithm used to calculate it
+   */
+  @autoserialize
+  checkSum: {
+    checkSumAlgorithm: string;
+    value: string;
+  };
+
   /**
    * The description of this Bitstream
    */

src/app/item-page/full/field-components/file-section/full-file-section.component.html

@@ -23,8 +23,8 @@ <h3 class="h5 simple-view-element-header">{{"item.page.filesection.original.bund
                             <dd class="col-md-8">{{(file.sizeBytes) | dsFileSize }}</dd>
 
 
-                            <dt class="col-md-4">{{"item.page.filesection.format" | translate}}</dt>
-                            <dd class="col-md-8">{{(file.format | async)?.payload?.description}}</dd>
+                            <dt class="col-md-4">{{"item.page.filesection.checksum" | translate}}</dt>
+                            <dd class="col-md-8">{{ file?.checkSum?.checkSumAlgorithm }}: {{ file?.checkSum?.value }}</dd>
 
                           <ng-container *ngIf="file.hasMetadata('dc.description')">
                             <dt class="col-md-4">{{"item.page.filesection.description" | translate}}</dt>
@@ -64,8 +64,8 @@ <h3 class="h5 simple-view-element-header">{{"item.page.filesection.license.bundl
                             <dt class="col-md-4">{{"item.page.filesection.size" | translate}}</dt>
                             <dd class="col-md-8">{{(file.sizeBytes) | dsFileSize }}</dd>
 
-                            <dt class="col-md-4">{{"item.page.filesection.format" | translate}}</dt>
-                            <dd class="col-md-8">{{(file.format | async)?.payload?.description}}</dd>
+                            <dt class="col-md-4">{{"item.page.filesection.checksum" | translate}}</dt>
+                            <dd class="col-md-8">{{ file?.checkSum?.checkSumAlgorithm }}: {{ file?.checkSum?.value }}</dd>
 
 
                             <dt class="col-md-4">{{"item.page.filesection.description" | translate}}</dt>

src/assets/i18n/en.json5

@@ -2806,6 +2806,8 @@
 
   "item.page.files": "Files",
 
+  "item.page.filesection.checksum": "File checksum:",
+
   "item.page.filesection.description": "Description:",
 
   "item.page.filesection.download": "Download",