Adding in new X-Aleo-SDK-Version header

[Pauan]

When the SDK makes a request to the server, this automatically adds in an X-Aleo-SDK-Version header, so the server can identify whether the request came from the SDK or not.

Fixes https://github.com/AleoHQ/explorer-monorepo/issues/14

[Pauan]

There are a few things that must be done before this is merged:

• The Wasm functions should also send the header
• The header should be customizable for ProgramManager
• Add in unit tests
• Somehow make the version not hardcoded

[Pauan]

This is now ready for review:

• The Wasm functions call SnarkVM functions, so that can't be fixed in this PR.
• Making the header customizable is a breaking change that must be done in a different PR.
• I added in unit tests.
• The version is no longer hardcoded.