Initialize default environement for debugger.

[karliss]

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Detailed description

Initialize io->envprofile so that default environment variables during debugging aren't empty. Rizin does more or less the same thing in rz_main_rizin.

Test plan (required)

• open /usr/bin/env
• start debugging
• press continue a until program exits
• inspect output in console
• Expected-> the env executable printed a bunch of environment variables

Closing issues
Closes #3408