feat(search): add date filters for created and updated fields in advanced search

[sreeshanth-soma]

Closes #80

Summary

Adds date-based advanced search filters for media in the sidebar, with support for both Created Date and Last Updated Date.

Changes

Backend

core/models/media_model.php

• Added created and updated to allowed advanced-search filters.
• Added SQL column mapping for:
  • created -> media.created
  • updated -> media.updated
• Added day-aware date comparison handling for advanced filters:
  • is / eq: matches records within that full day
  • not / neq: excludes that full day
  • gte / lte / gt / lt: compares using day boundaries
• Preserves existing operator behavior for non-date filters.

Frontend

public/html/sidebar/advanced_search.html

• Added new filter options:
  • Created Date
  • Last Updated Date
• Added date operator dropdown:
  • is on
  • is not on
  • is on or after
  • is on or before
• Added date input field (type="date") for date filters.

public/js/sidebar.js

• Added validation for date filter values (YYYY-MM-DD).
• Added date filter description rendering in criteria list.

Behavior

• Advanced Search now supports filtering media by:
  • Created Date
  • Last Updated Date
• Date comparisons operate on full calendar days (not raw timestamp equality).
• Existing simple search and non-date advanced filters are unchanged.

Verification

• Open Sidebar -> Media -> Advanced Search.
• Select Created Date, choose each operator (is on, is not on, is on or after, is on or before), set a date, and run search.
• Repeat with Last Updated Date.
• Confirm criteria chips/descriptions appear correctly and results match expected date-based behavior.
• Confirm no regressions for existing advanced filters (artist/title/year/duration/etc.).

[radiorob]

Ensure that inputting the date is the same smart logic\process, such as scheduling items. ie Not a picker.

[sreeshanth-soma]

You are absolutely right about that. I have replaced the native date picker with the component, so it now uses the exact same smart date parsing logic as the scheduling items.