refactor: migrate bundled lib dependencies to Composer

[anonymoususer72041]

This PR replaces bundled third-party libraries under lib/ with Composer-managed dependencies where this could be done without broader functional changes.

The bundled FPDF copy was replaced with setasign/fpdf and the bundled Sphinx PHP API was replaced with neutron/sphinxsearch-api. Related runtime includes and paths were updated accordingly.

lib/artichow is intentionally not part of this migration. It is still actively used by the current graph generation code and does not have a straightforward Composer-based replacement in this context.

The Sphinx client package used here is unmaintained, so this should be understood as a dependency management improvement, not as a long-term modernization of the Sphinx integration.

[RussH]

Good cleanup direction here — replacing the old FPDF/Sphinx files with Composer-managed dependencies makes sense, and removing FPDF code is food - going towards PHP 8.x.

A few things I think need fixing before merge:

• setasign/fpdf now requires ext-gd and ext-zlib, so we need to confirm/update the PHP/CI environment so composer install does not fail where GD is missing.
• ReportsUI.php no longer explicitly includes FPDF. That is fine only if vendor/autoload.php is guaranteed to be loaded globally before generateJobOrderReportPDF() runs; otherwise this will fatal with Class 'FPDF' not found.
• config/sphinx/sphinx.conf now hard-codes /usr/local/www/catsone.com/data/config/sphinx/STOPWORDS, which makes the config non-portable for normal installs/dev/CI. This probably needs to be changed, documented, or left as a path the installer/admin updates.

Can you take a look and see what clean-up can be done merging?

[anonymoususer72041]

• setasign/fpdf now requires ext-gd and ext-zlib, so we need to confirm/update the PHP/CI environment so composer install does not fail where GD is missing.

I will push a tiny fix for that.

I wonder how we want to deal with legacy travis CI? Is there any specific reason why travis is still in this repo, @RussH?

• ReportsUI.php no longer explicitly includes FPDF. That is fine only if vendor/autoload.php is guaranteed to be loaded globally before generateJobOrderReportPDF() runs; otherwise this will fatal with Class 'FPDF' not found.

I mixed this up with another unpublished branch of mine where I change OpenCATS to PSR-4. I will fix this also in this PR.