[WIP] Fix resource listing sorting error with computed fields

[Copilot]

• Explore repository structure and understand the issue
• Identify root cause: ResourceListingController doesn't validate if sort field is sortable
• Examine Blueprint columns API to check sortability
• Create method to get first sortable column from blueprint
• Update ResourceListingController to use sortable column validation
• Add test for computed field sorting error scenario
• Run tests to validate fix
• Run full test suite to ensure no regressions
• Code review (passed with no issues)
• Security check (CodeQL - passed)

Summary

Fixed the issue where viewing a resource listing with a computed field as the first listable column causes a MySQL error "Unknown column in 'order clause'".

Solution

• Added field sortability validation in Resource class
• Updated ResourceListingController to validate sort fields before use
• Non-sortable fields (computed, appended, relationships) now gracefully fall back to sortable columns
• All tests passing with comprehensive coverage of the fix

Original prompt

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This section details on the original issue you should resolve

<issue_title>Resource Listing sorting error when using computed field</issue_title>
<issue_description>### Description

When using a Title attribute on a resource model, a Unknown column 'title' in 'order clause' error is thrown when viewing the resource listing. (/cp/runway/resource)

I tried setting order_by in the resource config, however it looks like the initial sort field ($request->input('sort')) uses the first field in the blueprint (title).

\App\Models\Response::class => [
    'name' => 'Responses',
    'cp_icon' => 'drawer-file',
    'order_by' => 'created_at',
    'title_field' => 'title',
],

A workaround for this is simply moving my created_at field before the title field in my blueprint.

        fields:
          -
            handle: created_at
            field:
              type: date
              display: Date
              listable: true
              default: now
              validate:
                - required
              format: 'Y-m-d H:i:s'
              visibility: read_only
          -
            handle: title
            field:
              type: text
              display: Title
              visibility: computed
              sortable: false
              listable: true

Note: This error returns when using a MySQL db. SQLite appears to be more forgiving and doesn't throw an error, hence why I only had this issue on my staging server.

Steps to reproduce

1. Use MySQL db
2. Migrate a resource with no Title column
3. Add a Title attribute in the resource model
4. View resource listing in CP

Environment

Environment
Application Name: Change Helm
Laravel Version: 12.44.0
PHP Version: 8.3.27
Composer Version: 2.8.11
Environment: local
Debug Mode: ENABLED
URL: changehelm.test
Maintenance Mode: OFF
Timezone: UTC
Locale: en

Cache
Config: CACHED
Events: NOT CACHED
Routes: NOT CACHED
Views: CACHED

Drivers
Broadcasting: log
Cache: file
Database: sqlite
Logs: stack / single
Mail: smtp
Queue: sync
Session: file

Storage
public/storage: NOT LINKED

Livewire
Livewire: v3.6.4

Statamic
Addons: 9
Sites: 1
Stache Watcher: Enabled (auto)
Static Caching: Disabled
Version: 6.0.0-alpha.20 PRO

Statamic Addons
jacksleight/statamic-bard-mutator: 3.0.5
jacksleight/statamic-bard-texstyle: dev-feature/statamic-6
marcorieser/statamic-livewire: dev-statamic-6
marcorieser/tailwind-merge-statamic: dev-statamic-6
statamic-rad-pack/runway: 9.0.0-alpha.4
studio1902/statamic-peak-browser-appearance: dev-statamic-6
studio1902/statamic-peak-commands: 2.2
studio1902/statamic-peak-seo: dev-statamic-6
studio1902/statamic-peak-tools: dev-statamic-6</issue_description>

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

@duncanmcclean I'm struggling to reproduce this with a MySQL database. Are you able to provide the full stack trace for the error?

• Fixes Resource Listing sorting error when using computed field #759

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[duncanmcclean]

@copilot We should only sort by the title column when it's not marked as computed. Please reduce the diff to only whats needed to make this change.

[duncanmcclean]

Ugh too many changes. Gonna loop back to this myself when I have more time.