VM provisioning with correct initramfs

[jorisvilardell]

Context

When a pending job is submitted, provision a new VM using the initramfs image corresponding to the requested language.

Tasks

Acceptance Criteria:**

• Looks up language in supported_languages to find initramfs path
• Loads correct {language}-{version}.cpio.gz from backend/tmp/
• Launches VM with that initramfs
• Updates job status to Running

Related Code:**

• virt/src/bin/run_vm.rs - VM launching logic
• src/main.rs - Job polling/background task