fix(api): enable ilike filter for REST API search

[vcnainala]

Summary

• Add ilike to allowed Lomkit REST API search filter operators for PostgreSQL case-insensitive matching
• Extend Lomkit SearchRequest validation via dedicated App\Http\Requests\Rest\SearchRequest and custom search rules
• No custom query builder required — Laravel's PostgreSQL grammar already handles ilike once validation passes

Closes #335

Supersedes the closed PR #398, which targeted an older Lomkit API and included unnecessary CustomBuilder wiring.

Test plan

• php artisan test --filter=MoleculeSearchIlike
• ilike matches case-insensitively (e.g. %caffeine% finds Caffeine)
• like remains case-sensitive on PostgreSQL
• Unknown operators return 422 validation error

[codecov-commenter]

Codecov Report

❌ Patch coverage is 95.83333% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 7.07%. Comparing base (4223a58) to head (25a53d5).

Files with missing lines	Patch %	Lines
app/Rules/Search/SearchFilter.php	94.59%	2 Missing ⚠️

Additional details and impacted files

@@               Coverage Diff                @@
##             development    #806      +/-   ##
================================================
+ Coverage           6.13%   7.07%   +0.93%     
- Complexity          1737    1744       +7     
================================================
  Files                227     230       +3     
  Lines               8961    9008      +47     
================================================
+ Hits                 550     637      +87     
+ Misses              8411    8371      -40     

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.