fix: make frontend web dev script cross-platform

[DS123-ally]

Summary

• replace the POSIX-only VITE_NO_ELECTRON=1 vite ... dev:web script with a small Node launcher
• keep VITE_NO_ELECTRON=1 behavior while allowing extra Vite arguments to pass through
• document frontend source-development commands and the Windows npm.cmd workaround

Why

Windows PowerShell/cmd do not support VAR=value command syntax, so npm run dev:web fails for Windows contributors before Vite can start. The launcher sets the environment through Node instead of depending on shell-specific syntax.

Fixes # 2981

Validation

• npm.cmd run dev:web -- --host 127.0.0.1 --port 5185 --strictPort reached Vite ready state on Windows
• npm.cmd run typecheck

[somewherelostt]

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• @Pulkit7070

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