[browser] rename test-main.mjs

[pavelsavara]

so that V8 testing works without --module

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[Copilot]

Pull request overview

This PR renames the WASM test runner entrypoint from test-main.js to test-main.mjs so V8 can treat it as an ES module by default (avoiding the need for --module).

Changes:

• Update HTML entrypoints and build/test infrastructure to reference test-main.mjs instead of test-main.js.
• Update various MSBuild project properties/items that copy or point to the test runner JS file.
• Update logging/comments in the browser runtime/test harness to reflect the new filename and align formatting.

Reviewed changes

Copilot reviewed 15 out of 15 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
src/tests/Common/wasm-test-runner/index.html	Update module script reference to test-main.mjs.
src/tests/Common/wasm-test-runner/WasmTestRunner.proj	Point WasmMainJSPath at test-main.mjs in runtime-test/.
src/tests/Common/Directory.Build.targets	Copy test-main.mjs into $(CORE_ROOT)\runtime-test\.
src/mono/wasm/data/aot-tests/ProxyProjectForAOTOnHelix.proj	Update WasmMainJSPath to test-main.mjs.
src/mono/wasm/Wasm.Build.Tests/Wasm.Build.Tests.csproj	Copy test-main.mjs to test output instead of test-main.js.
src/mono/wasi/Wasi.Build.Tests/BuildTestBase.cs	Copy test-main.mjs into generated temp projects.
src/mono/sample/wasm/browser-bench/Console/Wasm.Console.Bench.Sample.csproj	Update WasmMainJSPath to test-main.mjs.
src/mono/sample/wasm/browser-bench/Console/Makefile	Update MAIN_JS to test-main.mjs.
src/mono/browser/test-main.mjs	Update log string to reflect .mjs name.
src/mono/browser/test-index.html	Update module script reference to test-main.mjs.
src/mono/browser/runtime/loader/globals.ts	Update “keep in sync” comment and minor formatting.
src/mono/browser/runtime/globals.ts	Update “keep in sync” comment and minor formatting.
eng/testing/tests.browser.targets	Copy/link test-main.mjs to wwwroot and default WasmMainJSPath to .mjs.
eng/testing/WasmRunnerTemplate.sh	Default --js-file to test-main.mjs.
eng/testing/WasmRunnerTemplate.cmd	Default --js-file to test-main.mjs.

[Copilot]

BuildProject now copies test-main.mjs from AppContext.BaseDirectory, but Wasi.Build.Tests doesn't appear to include test-main.mjs as a copied test asset (unlike Wasm.Build.Tests.csproj, which explicitly copies it). This will likely throw FileNotFoundException when creating the temp project. Add test-main.mjs to the test output (e.g., via a <None Include="$(BrowserProjectRoot)\test-main.mjs" CopyToOutputDirectory=... /> in the Wasi.Build.Tests project/imported targets), or adjust the copy source to a path that is guaranteed to exist.

Suggested change

	File.Copy(Path.Combine(AppContext.BaseDirectory, "test-main.mjs"),
	Path.Combine(_projectDir, "test-main.mjs"));
	string? sourceTestMainPath = Directory
	.EnumerateFiles(AppContext.BaseDirectory, "test-main.mjs", SearchOption.AllDirectories)
	.FirstOrDefault();
	if (sourceTestMainPath is null)
	throw new XunitException($"Could not find 'test-main.mjs' under '{AppContext.BaseDirectory}'.");
	File.Copy(sourceTestMainPath, Path.Combine(_projectDir, "test-main.mjs"));