feat(search): Implement 'Copyright Owner' filter in advanced search by joinin…

[sreeshanth-soma]

Closes #130

Summary

Adds a "Copyright Owner" filter to Advanced Search, allowing users to search media by the username of the user who claimed copyright ownership.

This enables searching for media owned and explicitly marked as copyrighted by a specific user.

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Changes

Backend

File: core/models/media_model.php

• Added copyright_owner to $allowed_filters in advanced search validation.
• Added column mapping:
  • copyright_owner → users.username
• Added:

  LEFT JOIN users ON media.owner_id = users.id

  in search() to allow filtering by user data.
• When the copyright_owner filter is applied, automatically enforces:

  media.is_copyright_owner = 1

• Preserves all existing behavior for other filters and operators.

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Frontend

File: public/html/sidebar/advanced_search.html

• Added new filter option:
  • Copyright Owner
• Uses standard text operators:
  • contains
  • does not contain
  • is exactly
  • is not
• Uses a standard text input field for the user name.

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Behavior

Advanced Search now supports filtering media by:

• Copyright Owner (username)

The filter matches:

users.username LIKE ...
AND media.is_copyright_owner = 1

Other search functionality (simple search and existing advanced filters) remains unchanged.

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Verification Steps

• Open Sidebar → Media → Advanced Search
• Select Copyright Owner
• Test each operator:
  • contains
  • does not contain
  • is exactly
  • is not
• Enter a valid username and run search
• Confirm the criteria description renders correctly
• Confirm results only include media where:
  • The matching user is the owner
  • is_copyright_owner = 1
• Confirm no regressions for existing filters (artist, title, year, duration, etc.)