[browser][mono] simplify internal testing switches

[pavelsavara]

transforming those from API methods to flags, allows independent JS module other than dotnet.js to implement the functionality.

Contributes to #101169

[dotnet-policy-service]

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[Copilot]

Pull request overview

This PR refactors internal testing switches from dedicated API methods to configuration flags, enabling independent JavaScript modules (not just dotnet.js) to implement the functionality. This is part of the effort to modularize the WebAssembly runtime initialization.

Key changes:

• Removed dedicated API methods like withElementOnExit(), withConsoleForwarding(), withExitCodeLogging(), etc.
• Replaced them with a unified .withConfig() approach accepting configuration flags
• Updated installUnhandledErrorHandler() to be called conditionally based on the config flag rather than within a method

Reviewed changes

Copilot reviewed 17 out of 17 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
src/tests/FunctionalTests/WebAssembly/Browser/HotReload/main.js	Converts .withElementOnExit() to .withConfig({ appendElementOnExit: true })
src/mono/wasm/testassets/WasmOnAspNetCore/WasmBrowserClient/wwwroot/main.js	Consolidates three method calls into a single .withConfig() call with three flags
src/mono/wasm/testassets/WasmBasicTestApp/App/wwwroot/main.js	Replaces multiple chained method calls with unified config object approach
src/mono/wasm/Wasm.Build.Tests/Templates/WasmTemplateTestsBase.cs	Updates C# test template generation to use new config syntax
src/mono/sample/wasm/browser/wwwroot/main.js	Converts testing switch methods to config flags
src/mono/sample/wasm/browser-threads/wwwroot/main.js	Merges testing flags into existing .withConfig() call
src/mono/sample/wasm/browser-shutdown/wwwroot/main.js	Replaces .withOnConfigLoaded() with .withModuleConfig({ onConfigLoaded: ... })
src/mono/sample/wasm/browser-profile/wwwroot/main.js	Moves testing flags into existing config object
src/mono/sample/wasm/browser-logprofile/wwwroot/main.js	Consolidates testing switches and fixes spacing in unrelated line
src/mono/sample/wasm/browser-eventpipe/wwwroot/main.js	Converts two method calls to config flags
src/mono/sample/wasm/browser-bench/wwwroot/main.js	Removes two method calls and adds config flags (incomplete migration)
src/mono/sample/wasm/browser-advanced/wwwroot/main.js	Moves testing flag into existing config object
src/mono/sample/wasm/Directory.Build.targets	Adds additional nested build properties for better build configuration
src/mono/browser/test-main.js	Consolidates multiple testing method calls into unified config object
src/mono/browser/runtime/types/internal.ts	Removes obsolete linkerEnabled field from internal config type
src/mono/browser/runtime/loader/run.ts	Removes API methods and moves installUnhandledErrorHandler() call to be conditional on config flag
src/libraries/sendtohelix-browser.targets	Updates comment to reference new config flag name instead of old method name