[eas-cli] Use an isolated env for local builds

[ramonclaudio]

Stacked on #4229.

Why

eas build --local passes every var from the shell to the local-build plugin, which can make local builds behave differently from EAS Build.

How

I updated the local-build plugin process to start with an isolated env, then added the EAS env, local runtime vars, and the local build settings it needs.

Test Plan

Tests, package checks, and local Android and iOS builds pass.

[linear-code]

DVT-119

[codecov]

Codecov Report

❌ Patch coverage is 88.88889% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 63.91%. Comparing base (b0bb4d2) to head (c25f8b3).

Files with missing lines	Patch %	Lines
packages/eas-cli/src/build/local.ts	88.89%	0 Missing and 2 partials ⚠️

Additional details and impacted files

@@                            Coverage Diff                             @@
##           @ramonclaudio/dvt-119-eas-cli-env-mode    #4244      +/-   ##
==========================================================================
+ Coverage                                   63.90%   63.91%   +0.01%     
==========================================================================
  Files                                        1033     1033              
  Lines                                       47555    47566      +11     
  Branches                                    10002    10004       +2     
==========================================================================
+ Hits                                        30384    30395      +11     
+ Misses                                      17070    17069       -1     
- Partials                                      101      102       +1     

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[github-actions]

Subscribed to pull request

File Patterns	Mentions
packages/eas-cli/**	@douglowder
packages/eas-cli/src/build/**	@sjchmiela

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[kitten]

EXPO_UNSAFE_DOTENV_KEYS and this utility is something I'm not familiar with 🤔 maybe @sjchmiela or @szdziedzic can evaluate this better. I believe, this may be similar to a utility for original-env we have in @expo/env, so not sure if we need to reconsolidate?

[kitten]

Revisiting this; assuming we're keeping parity here with EAS Build, is there any way we could just not inherit any env vars and issue a major bump? It might be easier to build up parity than it is to try to pass through filtered process.env vars, and treat the spawned sub-process as "isolated"

[ramonclaudio]

Yea, that makes sense! I tested local ios and android builds with the runtime var list I added, but can we confirm these are all the vars we want to keep in the isolated env?

https://github.com/expo/eas-cli/pull/4244/changes#diff-a54f38cd6a574317f91ba14ef751c1868db0d9469f924f18b018222c1c956a6aR18-R33

[github-actions]

✅ Thank you for adding the changelog entry!