fix: Several new worklist issues (#6130)

* fix: Several new worklist issues

* refactor: Export a single OnStudyDoubleClick type from the StudyList barrel

Addresses PR review feedback: the double-click handler signature was
written out in both TableProps and the WorkList customization cast,
so the two could drift apart.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

* feat: Run worklist study double-click as a command, registrable by modes

- Modes can now export getCommandsModule on their definition; appInit
  registers it (via the new ExtensionManager.registerCommandsModule)
  before the mode is instantiated, in a new 'WORKLIST' commands context,
  so the commands are available on the worklist before any mode route
  is entered.
- The workList.onStudyDoubleClick customization is now a command run
  input (name/options) instead of a bare function, defaulting to the
  new launchDefaultMode command, which launches the default workflow
  falling back to the first applicable one. commandOptions.workflowId
  overrides it to a specific mode.
- Duplicate mode ids are now skipped before running their modeFactory
  rather than after.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

platform/core/src/extensions/ExtensionManager.ts

@@ -614,6 +614,24 @@ export default class ExtensionManager extends PubSubService {
     });
   }
 
+  /**
+   * Registers a commands module produced outside the extension registration
+   * path — e.g. a mode's `getCommandsModule`, registered at app init so its
+   * commands are available before any mode route is entered (worklist time).
+   *
+   * @param commandsModule - as returned by a `getCommandsModule` function
+   * @param defaultContext - context used when the module does not declare one
+   */
+  public registerCommandsModule(
+    commandsModule: CommandsModule,
+    defaultContext: string = 'VIEWER'
+  ): void {
+    this._initCommandsModule({
+      ...commandsModule,
+      defaultContext: commandsModule.defaultContext || defaultContext,
+    });
+  }
+
   /**
    *
    * @private