feat: gather config dependencies when config is a js_library

[sallustfire]

Allows esbuild config attribute to accept a js_library target, automatically including its dependencies (e.g., esbuild plugins) in the build without manually adding them to srcs.

This fixes the issue where config files with dependencies required users to manually specify those dependencies in the esbuild rule's srcs attribute.

Changes are visible to end-users: yes

• Searched for relevant documentation and updated as needed: no
• Breaking change (forces users to change their own code or config): no
• Suggested release notes appear below: yes

config files have their transitive dependencies propagated to esbuild

Test plan

• Covered by existing test cases which were extended

[aspect-workflows]

Test (Bazel 7) (Test)

All tests were cache hits

18 tests (100.0%) were fully cached saving 1s.

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Test (Bazel 8) (Test)

All tests were cache hits

18 tests (100.0%) were fully cached saving 849ms.

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Test (Bazel 7) (Test)

e2e/bundle

All tests were cache hits

2 tests (100.0%) were fully cached saving 96ms.

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Test (Bazel 8) (Test)

e2e/bundle

All tests were cache hits

2 tests (100.0%) were fully cached saving 110ms.

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Test (Bazel 7) (Test)

e2e/custom_version

All tests were cache hits

2 tests (100.0%) were fully cached saving 156ms.

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Test (Bazel 8) (Test)

e2e/custom_version

All tests were cache hits

2 tests (100.0%) were fully cached saving 161ms.

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Test (Bazel 7) (Test)

e2e/npm-links

All tests were cache hits

2 tests (100.0%) were fully cached saving 107ms.

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Test (Bazel 8) (Test)

e2e/npm-links

All tests were cache hits

2 tests (100.0%) were fully cached saving 94ms.

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Test (Bazel 7) (Test)

e2e/smoke

All tests were cache hits

1 test (100.0%) was fully cached saving 31ms.

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Test (Bazel 8) (Test)

e2e/smoke

All tests were cache hits

1 test (100.0%) was fully cached saving 26ms.

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Test (Bazel 7) (Test)

e2e/sourcemaps

All tests were cache hits

7 tests (100.0%) were fully cached saving 313ms.

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Test (Bazel 8) (Test)

e2e/sourcemaps

All tests were cache hits

7 tests (100.0%) were fully cached saving 335ms.

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Test (Bazel 7) (Test)

e2e/toolchain_from_source

All tests were cache hits

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Test (Bazel 8) (Test)

e2e/toolchain_from_source

All tests were cache hits

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Test (Bazel 7) (Test)

e2e/tsconfig

All tests were cache hits

3 tests (100.0%) were fully cached saving 135ms.

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Test (Bazel 8) (Test)

e2e/tsconfig

All tests were cache hits

3 tests (100.0%) were fully cached saving 165ms.

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