Add runtime capability scaffolding and align docs

tests/test_vm_firecracker.py

@@ -0,0 +1,51 @@
+from __future__ import annotations
+
+import json
+from dataclasses import dataclass, field
+from pathlib import Path
+from typing import Any
+
+from pyro_mcp.vm_firecracker import build_launch_plan
+from pyro_mcp.vm_network import NetworkConfig
+
+
+@dataclass
+class StubInstance:
+    vm_id: str
+    vcpu_count: int
+    mem_mib: int
+    workdir: Path
+    metadata: dict[str, str] = field(default_factory=dict)
+    network: Any = None
+
+
+def test_build_launch_plan_writes_expected_files(tmp_path: Path) -> None:
+    instance = StubInstance(
+        vm_id="abcdef123456",
+        vcpu_count=2,
+        mem_mib=2048,
+        workdir=tmp_path,
+        metadata={
+            "kernel_image": "/bundle/profiles/debian-git/vmlinux",
+            "rootfs_image": "/bundle/profiles/debian-git/rootfs.ext4",
+        },
+        network=NetworkConfig(
+            vm_id="abcdef123456",
+            tap_name="pyroabcdef12",
+            guest_ip="172.29.100.2",
+            gateway_ip="172.29.100.1",
+            subnet_cidr="172.29.100.0/24",
+            mac_address="06:00:ab:cd:ef:12",
+        ),
+    )
+
+    plan = build_launch_plan(instance)
+
+    assert plan.config_path.exists()
+    assert plan.guest_network_path.exists()
+    assert plan.guest_exec_path.exists()
+    rendered = json.loads(plan.config_path.read_text(encoding="utf-8"))
+    assert rendered["machine-config"]["vcpu_count"] == 2
+    assert rendered["network-interfaces"][0]["host_dev_name"] == "pyroabcdef12"
+    guest_exec = json.loads(plan.guest_exec_path.read_text(encoding="utf-8"))
+    assert guest_exec["transport"] == "vsock"