[wasm] Determine what default value to use for `$(EmccInitialHeapSize)`

[radical]

Currently we use 512M. Is this really required? It might not be available for some mobile devices.
@lewing suggests that maybe we should use whatever amount a simple blazor app would need, plus some more.

Thoughts?

cc @radekdoulik @kg @pranavkm

context: #66233 (comment)

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Issue Details

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Currently we use 512M. Is this really required? It might not be available for some mobile devices.
@lewing suggests that maybe we should use whatever amount a simple blazor app would need, plus some more.

Thoughts?

cc @radekdoulik @kg @pranavkm

Author:	radical
Assignees:	-
Labels:	arch-wasm
Milestone:	-

[kg]

Do we think this needs to happen for 7? I think since the tooling story for this has improved, it might be fine to leave it as-is. I'm also not sure whether it makes sense to change it late in the cycle vs in a preview when we can hear from users about whether it's causing issues.

[radical]

I agree. Moving to 8.0 . @lewing please change if you think we should try something here