Function validate_manifest 

pub fn validate_manifest(
    manifest: &SnapshotManifest,
    expected_arch: &str,
    expected_memory_size: u64,
    expected_vp_count: u32,
    expected_page_size: u32,
) -> Result<()>

Validate that a snapshot manifest is compatible with the running VM config.

Checks version, architecture, memory size, VP count, and page size. Returns Ok(()) if the manifest matches, or an error describing the first mismatch found.