feat: Allow filtering by platform on workflow call

[juanjosevazquezgil]

Closes https://github.com/prefapp/features/issues/831

Examples (platforms)

Build for platform linux/amd64:

• build_images.yaml: https://github.com/jvazquez-prefapp/build-and-dispatch/blob/7ea76880870a8e818b306ef300c942e8a6304bfe/.github/build_images.yaml#L7
• Workflow: https://github.com/jvazquez-prefapp/build-and-dispatch/blob/5685e3d9e4d754cb4364b53d40338ae32034bed2/.github/workflows/test-build-and-dispatch-docker-images.yaml#L44
• Action run: https://github.com/jvazquez-prefapp/build-and-dispatch/actions/runs/22388088642/job/64803039568#step:8:462

Build for all platforms using *:

• build_images: https://github.com/jvazquez-prefapp/build-and-dispatch/blob/7ea76880870a8e818b306ef300c942e8a6304bfe/.github/build_images.yaml#L7
• Workflow: https://github.com/jvazquez-prefapp/build-and-dispatch/blob/dd7923c6afeec27167b25a3f1b643d6feead2021/.github/workflows/test-build-and-dispatch-docker-images.yaml#L44
• Action run: https://github.com/jvazquez-prefapp/build-and-dispatch/actions/runs/22388420579/job/64804116140#step:8:466

Default (also builds for all platforms when no platforms attribute is set):

• build_images: https://github.com/jvazquez-prefapp/build-and-dispatch/blob/7ea76880870a8e818b306ef300c942e8a6304bfe/.github/build_images.yaml#L7
• Workflow: https://github.com/jvazquez-prefapp/build-and-dispatch/blob/64fabfaa26ab4ec44033d02a3c9f6cf668608244/.github/workflows/test-build-and-dispatch-docker-images.yaml#L37-L43
• Action run: https://github.com/jvazquez-prefapp/build-and-dispatch/actions/runs/22388597014/job/64804680351#step:8:462

No flavors to build after filtering:

• build_images: https://github.com/jvazquez-prefapp/build-and-dispatch/blob/4492fb2782cee60d59142e9b6cad7f31a0d55410/.github/build_images.yaml#L6
• Workflow: https://github.com/jvazquez-prefapp/build-and-dispatch/blob/a64941f05e6536f57f6bafca41cb69ff0d5c0fb5/.github/workflows/test-build-and-dispatch-docker-images.yaml#L44
• Action run: https://github.com/jvazquez-prefapp/build-and-dispatch/actions/runs/22441981765

Examples (runs_on)

Default (no value for runs_on):

• Workflow: https://github.com/jvazquez-prefapp/build-and-dispatch/blob/ead2353d6c9d54909ea2cc46501be9cc4c381b4c/.github/workflows/test-build-and-dispatch-docker-images.yaml
• Action run: https://github.com/jvazquez-prefapp/build-and-dispatch/actions/runs/22354793386/job/64691267196#step:1:16

runs_on with value:

• Workflow: https://github.com/jvazquez-prefapp/build-and-dispatch/blob/cb91c8edf2c712eb2dd028495bb083ea9f3fd74e/.github/workflows/test-build-and-dispatch-docker-images.yaml#L45
• Action run: https://github.com/jvazquez-prefapp/build-and-dispatch/actions/runs/22354991869/job/64692003411#step:1:16

[Copilot]

Pull request overview

This PR adds the ability to filter which platforms (e.g., linux/amd64, linux/arm64) to build for when calling the build_images workflow. This allows callers to selectively build images for specific platforms rather than always building for all platforms defined in the configuration.

Changes:

• Added a new platforms input parameter to the GitHub workflow with wildcard (*) or comma-separated platform list support
• Implemented platform filtering logic that intersects requested platforms with each flavor's configured platforms
• Added platforms property to the BuildImages class to store and access the platform filter

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 4 comments.

File	Description
.github/workflows/build_images.yaml	Added new platforms input parameter with default "*" and passes it to the workflow execution
firestarter/workflows/build_images/build_images.py	Implemented platform filtering logic including platforms property, check_if_build_all_platforms method, and intersection-based filtering in compile_images_for_all_flavors
firestarter/tests/test_build_images_functionality.py	Added platforms field to test variables to support the new BuildImages constructor parameter

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[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 4 comments.

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[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 6 comments.

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[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

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[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

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[Copilot]

The test for the wildcard platform '' is missing. While test_validate_platforms tests that '' is accepted as valid input, and test_compile_images_filtering_by_platform tests the filtering behavior with '', neither test explicitly verifies that validate_platforms('') returns '' correctly or that check_if_build_all_platforms() returns True when platforms is ''.

Consider adding a specific test case:

def test_check_if_build_all_platforms():
    builder._platforms = '*'
    assert builder.check_if_build_all_platforms() == True
    
    builder._platforms = 'linux/amd64'
    assert builder.check_if_build_all_platforms() == False

This would ensure the wildcard logic is explicitly tested, though the current indirect coverage through the integration test is sufficient for basic functionality.