[wasm] Unify boot config location

[maraf]

• We need both mono-config.json and blazor.boot.json schemas until we can use new SDK in tree
• Rename mono-config to blazor.boot.json to unify location where to load config from
• Drop the need for withStartupOptions to use Wasm SDK path in JS

[ghost]

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Issue Details

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• We need both mono-config.json and blazor.boot.json schemas until we can use new SDK in tree
• Rename mono-config to blazor.boot.json to unify location where to load config from
• Drops the need for withStartupOptions to use Wasm SDK

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

[pavelsavara]

This would be ugly merge, other than that look like acceptable temporary solution.

#85730

[maraf]

I can easily redo it after loader. Mostly text replaces