[browser][coreCLR] JS modules consistency via gitHash

[pavelsavara]

• Add gitHash into each JS file/module and check the consistency during startup
• This is fail fast for scenarios where HTTP cache or build folders contain inconsistent versions of JS files.

[dotnet-policy-service]

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[Copilot]

Pull request overview

This PR adds git hash consistency checking across JavaScript modules in the browser CoreCLR runtime. The implementation adds a gitHash to each JS module and validates during startup that all modules were built from the same git commit, providing fail-fast detection for scenarios where HTTP caches or build folders contain mismatched versions of JS files.

Key Changes:

• Imports GitHash from "consts:gitHash" in each module and exports it for runtime access
• Adds validation logic in dotnetInitializeModule functions to compare the loader's gitHash with each module's gitHash
• Updates footer.js files to export the gitHash and exclude it from automatic export iteration
• Changes corerun's gitHash from "corerun" to null to skip validation for development builds

Reviewed changes

Copilot reviewed 10 out of 10 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/native/libs/System.Runtime.InteropServices.JavaScript.Native/native/index.ts	Adds gitHash import, export, and consistency check comparing with DOTNET_INTEROP.gitHash
src/native/libs/System.Runtime.InteropServices.JavaScript.Native/native/cross-linked.ts	Declares DOTNET_INTEROP as a global constant
src/native/libs/System.Runtime.InteropServices.JavaScript.Native/libSystem.Runtime.InteropServices.JavaScript.Native.footer.js	Exports gitHash on DOTNET_INTEROP object and excludes it from export iteration
src/native/libs/System.Runtime.InteropServices.JavaScript.Native/interop/index.ts	Adds gitHash import and consistency check, refactors to get runtimeApi earlier for validation
src/native/libs/System.Native.Browser/utils/index.ts	Adds gitHash import and consistency check, moves initPolyfills after validation
src/native/libs/System.Native.Browser/native/index.ts	Adds gitHash import, export, and consistency check comparing with DOTNET.gitHash
src/native/libs/System.Native.Browser/libSystem.Native.Browser.footer.js	Exports gitHash on DOTNET object and excludes it from export iteration
src/native/libs/System.Native.Browser/diagnostics/index.ts	Adds gitHash import and consistency check
src/native/corehost/browserhost/host/index.ts	Adds gitHash import and consistency check after Object.assign
src/coreclr/hosts/corerun/wasm/libCorerun.extpost.js	Changes gitHash from "corerun" string to null to skip validation