[browser][coreCLR] reduce initial memory footprint

[pavelsavara]

Fixes #127880

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[Copilot]

Pull request overview

This PR reduces the default WebAssembly memory and stack settings used by the CoreCLR browser host, aiming to lower the initial memory footprint during startup (per #127880).

Changes:

• Decrease Emscripten INITIAL_MEMORY from 128 MB to 32 MB for browserhost.
• Decrease Emscripten STACK_SIZE from 5 MB to 2 MB for browserhost.
• Keep the MSBuild CoreCLR WASM relink targets in sync with the browserhost CMake configuration.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
src/native/corehost/browserhost/CMakeLists.txt	Lowers default INITIAL_MEMORY and STACK_SIZE link options for the browser host to reduce startup footprint.
src/mono/browser/build/BrowserWasmApp.CoreCLR.targets	Mirrors the updated memory/stack defaults in the CoreCLR WASM relink pipeline so app relinks match the host configuration.

[radekdoulik]

LGTM, let see if CI tests will pass. Thank you!

[jkotas]

There are more places where this is hardcoded:

src\mono\browser\browser.proj(219):<EmccStackSize>5MB</EmccStackSize>
src\mono\browser\build\BrowserWasmApp.targets(171):<EmccStackSize Condition="'$(EmccStackSize)' == ''">5MB</EmccStackSize>
src\mono\wasm\build\WasmApp.Common.targets(67):- $(EmccStackSize)                    - Stack size. Default value: 5MB.

Is this inconsistency intentional?

[pavelsavara]

Is this inconsistency intentional?

Yes, that is Mono

[jkotas]

What's the reasoning behind lower limits for CoreCLR? Is there a problem with applying the same lower limits to Mono as well?