feat(photos): expose image width/height on the /api/photos timeline

list_media_files now LEFT JOINs storage.file_metadata and returns each
photo's pixel dimensions next to the sort date. The endpoint wraps FileDto
in a flattened PhotoDto carrying width/height, so the gallery can lay tiles
out at their true aspect ratio (justified layout) without a second per-file
metadata round-trip and without layout shift. FileItem gains optional
width/height. No change to FileDto or its other construction sites.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01JW6ghFMDtnRYuYNzZhb47M

static/js/core/types.js

@@ -45,6 +45,8 @@
  * @property {number} size
  * @property {string} size_formatted
  * @property {number} sort_date
+ * @property {number} [width] original pixel width (photos timeline only)
+ * @property {number} [height] original pixel height (photos timeline only)
  * @property {string} etag opaque HTTP ETag, for If-Match / If-None-Match
  * @property {string} content_hash raw BLAKE3 content hash, for dedup checks
  * @property {string} [snippet] plain-text fragment around a content match (search results only)