[wasm] Add warning code to all warnings produced in WasmAppBuilder

[maraf]

• WASM0001 - All PInvoke related warnings
• WASM0002 - Missing CultureName metadata for satellite assembly
• WASM0003 - Found identical vfs mappings for target path
• WASM0004 - Loading assembly reference '..' for '..' failed

Fixes #78690

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Issue Details

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• WASM0001 - All PInvoke related warnings
• WASM0002 - Missing CultureName metadata for satellite assembly
• WASM0003 - Found identical vfs mappings for target path
• WASM0004 - Loading assembly reference '..' for '..' failed

Fixes #78690

Author:	maraf
Assignees:	maraf
Labels:	arch-wasm, area-Build-mono
Milestone:	8.0.0

[maraf]

@radical Should I add warning code even for this one?

runtime/src/tasks/WasmAppBuilder/EmccCompile.cs

Line 275 in 0fffb89

Log.LogWarning(reason);

[radical]

@radical Should I add warning code even for this one?

runtime/src/tasks/WasmAppBuilder/EmccCompile.cs

Line 275 in 0fffb89

Log.LogWarning(reason);

Good question. Remove the LogWarning. The caller will log the reason as a MessageImportance.Low message.
And change the message to the dependency file {inFile} needed for compiling {srcFile} to {outFile} could not be found., so it works better with the full message that is logged by the caller.

[radical]

@akoeplinger @steveisok do we need to document these new warning codes anywhere?

[akoeplinger]

do we need to document these new warning codes anywhere?

Yes but I think we also need to localize them if they're actually user-facing. I don't know if there's guidance/restrictions around coming up with new codes though.

[radical]

I have opened #79173 for following up on the localization, and documentation.

[radical]

The MacCatalyst failure is unrelated, and was - #78778 .

[maraf]

/backport to release/7.0

[github-actions]

Started backporting to release/7.0: https://github.com/dotnet/runtime/actions/runs/3622382639