build: add packaged FSDK CUPS drivers

[castrojo]

Summary

• add pinned FSDK elements for c2esp, Dymo, fxlinuxprint, Oki, pxljr, rastertosag-gdi, SpliX, brlaser, and P-Touch
• generate and expose each family's PPD archive or driver description through the running Printer Application
• declare direct interpreter, filter, helper-library, and shared-library ownership while excluding development-only payloads
• fix the FSDK cups-filters composite-option use-after-free and keep Ghostscript on its bundled zlib for reliable full-size IJS rendering
• exercise every filter family with deterministic printer-language output, including default Letter pxljr, Oki stdin raster, and both SpliX paths

Verification

• just validate
• just verify-core
• just verify-payload
• just verify-raster-drivers
• just verify-packaged-drivers
• just verify-cups-patch-chain
• actionlint .github/workflows/*.yml
• bash -n tests/*.sh files/*.sh
• git diff --check

The OCI image remains local and unpublished. This is a stacked PR based on feat/fsdk-raster-drivers (#3).