fix: determine esbuild binary path at repository instantiation (#234)

[sallustfire]

Migrates away from the deprecated @bazel_tools//src/conditions:host_windows condition by determining the correct esbuild binary path at repository instantiation time.

Since each esbuild repository is platform-specific (platform attribute is known when the repository is created), we can directly generate the correct path in the BUILD file without a select statement.

• Windows (win32-x64, windows-64): "package/esbuild.exe"
• Other platforms: "package/bin/esbuild"

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Changes are visible to end-users: no

Test plan

• Covered by existing test cases
• Manual testing; please provide instructions so we can reproduce:
  Manually tested that that legacy (< 0.16.0) windows platform naming still works

[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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