[build-tools] Load legacy command/path local functions and resolve module paths

[sswrk]

Why

How

Test Plan

[linear-code]

ENG-25402

[sswrk]

Warning

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• [eas-cli] Validate legacy command/path local functions referenced from workflows #4098
• [build-tools] Load legacy command/path local functions and resolve module paths #4097 👈 (View in Graphite)
• [steps][build-tools][eas-cli] Expand legacy command/path local functions to a single build step; rename references in the consumers #4096
• [eas-build-job][build-tools][steps] Accept legacy command/path custom function shape in function.yml; rename references in the consumers #4095
• [eas-cli][build-tools][steps] Validate local composite functions referenced from workflow hooks; extract the shared loader into steps #4064
• [build-tools][steps] Load composite function catalogs for hook steps #4063
• [steps] Support local composite functions in hook steps #4062
• [steps] Unify the default gating of steps with no if: across steps, composite scopes, and hooks #4061
• [eas-cli] Validate local composite functions in workflow files #3931
• [build-tools] Load local composite function catalog at build runtime #3930
• [steps][4/4] Resolve composite function outputs #4015
• [steps][3/4] Interpolate composite function inputs #4014
• [steps][2/4] Expand composite function references into build steps #3929 : 1 other dependent PR (#4013 )
• [steps][1/4] Add isCompositeFunctionPath and reject local composite functions in custom builds #3956
• [eas-build-job] Add local composite function schema #3928
• main

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[codecov]

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Additional details and impacted files

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##             szymonswierk/eng-25402-steps-expand-legacy-functions    #4097   +/-   ##
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[github-actions]

✅ Thank you for adding the changelog entry!

[sswrk]

Folding into #4096