* fix(server): Correctly set album start and end dates
Currently, the query that retrieves album assets uses
`ORDER BY assets.fileCreatedAt DESC`, which makes the existing logic
return the start/end dates reversed (with `startDate` being taken from
the first asset in the array).
Instead of using the index-based approach, this change iterates through
assets to get the min/max `fileCreatedAt`. This will avoid any future
issues, if the query ordering changes, or becomes customizable (e.g. in
case the user prefers to visualize older assets first).
* fix: Maintain constant cost and only swap variables if needed
