ci: align package workflow and PSE84 release

[IFX-Anusha]

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Description

Package Workflow Update

Summary

This PR updates the Infineon fork’s package, test, and release workflow after rebasing main onto the current ArduinoCore-zephyr upstream baseline.

The goal is to keep PSE84 integrated with the generic zephyr_contrib build/test flow while preserving an Infineon-controlled PSE84-only release channel.

CI Changes

• Feature-branch pushes now build, package, and test only kit_pse84_ai.
• Pull requests to main and pushes to main continue to run the complete all-board matrix.
• Packaging now uses the board matrix selected by CI, preventing PSE84-only branch runs from attempting to package firmware for unbuilt boards.
• Fork CI uses Arduino’s public main CI package index to install compatible Board Manager tools, including arm-zephyr-eabi 1.0.1.
• Core version generation now handles:
• tagless fork CI checkouts;
• non-core tool tags such as windows_toolchain_1.0.1;
• consistent version handoff from build-env to each board build job.

PSE84 Release Changes

• PSE84 remains inside generic zephyr_contrib for shared CI validation.

The PSE84 release workflow now:

• downloads the successful zephyr_contrib artifact;
• filters it to PSE84 board files, variant, firmware, and shared core content;
• publishes ArduinoCore-zephyr_pse84-.tar.bz2;
• publishes the matching package_infineon_pse84_index.json to the Infineon GitHub Release.
• This avoids publishing RA8D1/NXP/community-board content as part of an Infineon PSE84-only Boards Manager release.

Validation

• Full matrix CI passed before introducing the feature-branch optimization:
• all loader builds;
• all generated core packages;
• PSE84 static and dynamic sketch tests;
• generic zephyr_contrib board tests.
• PSE84-specific Zephyr patches apply cleanly on the rebased upstream Zephyr tree.
• Package workflow and release workflow YAML parse successfully.
• PSE84-only release archive filtering was tested locally against a mixed archive:
• includes PSE84 variant/firmware;
• excludes non-PSE84 variants/firmware.
• Feature-branch package filtering was tested locally:
• PSE84-only matrix creates a PSE84-only package; it no longer requests firmware for unbuilt boards.

Intentional Fork Differences

• package_core.yml uses Arduino’s public CI index as a temporary dependency source because this fork does not yet operate an Infineon-owned CI package-index service.
• get_core_version.sh includes tagless-fork robustness because upstream release tags are not mirrored to the Infineon fork.
• release_pse84.yml and package_pse84_release.sh remain fork-specific because they implement the independent Infineon PSE84 release channel.