Add back navigation and eliminate dialog delay in Album Manager

[Copilot]

Album Manager lacked navigation back to Settings, forcing users to close and reopen dialogs. Dialog opening was also delayed by synchronous album loading, allowing UMAP hover events to display thumbnails on top of the modal.

Changes

• Navigation: Added "← Settings" button in Album Manager header that returns to Settings dialog

  • Positioned top-left, styled with #faea0e theme color
  • Uses dynamic import to call openSettingsModal() from settings.js

• Performance: Show dialog immediately, defer album loading

  • Removed blocking showSpinner() call from open flow
  • Moved loadAlbums() and checkForOngoingIndexing() into setTimeout(..., 0)
  • Dialog becomes visible before async operations begin

async show() {
  // Show immediately
  this.overlay.classList.add("visible");
  
  // Defer heavy operations
  setTimeout(async () => {
    await this.loadAlbums();
    await this.checkForOngoingIndexing();
  }, 0);
}

Screenshots

Album Manager with back navigation:

Navigation flow:

Original prompt

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This section details on the original issue you should resolve

<issue_title>User interface improvements for Album Manager</issue_title>
<issue_description># Two UI refinements for the Album Manager UI

Add a back arrow to the album manager

To open the Album Manager UI, the user first opens the settings dialog and then clicks the "Manage Albums" button. However, once the AM dialog is open there is no way to return to the settings dialog. Instead, the user must close the AM dialog and then reopen the settings dialog. This is counterintuitive.

A better user interface would be to provide a left-arrow icon at the top-left of the AM dialog labeled "Settings". Click on the icon to return to the settings dialog.

Reduce delay when bringing up the AM dialog

When there are a large number of albums defined, there is a significant delay when clicking on the "Manage Albums" button. During this time hover events over the UMAP display can be triggered, causing thumbnail previews to display on top of the album manager dialog.

Please bring the AM dialog up as soon as possible and defer the generation of the album content until the dialog is visible to avoid this behavior.</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes User interface improvements for Album Manager #138

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[lstein]

Clean code and works as expected.