Merge main into fix/db-off-data-plane-469

Brings in main's 8 commits — #470 (backend-agnostic CI guards: BackendStatus
enum, quiet status(), is_backend_available/is_backend_ready, tests/_backend.py
skip_unless_backend) plus firecracker status() readiness checks (kvm/kernel/
dropbear/mke2fs).

Reconciled #470's additions into the reorg'd backend structure:
  * BackendStatus enum + the status(*, quiet=) ABC signature -> backend/base.py
  * is_backend_available / is_backend_ready -> backend/selection.py
  * exposed all three through the lazy backend facade (__init__).
Integration-test conflicts were our control_plane->orchestrator renames vs
main's skip_unless_docker -> skip_unless_backend swap: kept our refactored
import paths + main's guard. Repointed main's new is_backend_* tests to patch
selection._backends (our moved home) instead of the facade.

pyright: 0 errors. Full unit suite green (2272).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

tests/integration/test_gateway_image.py

@@ -25,14 +25,14 @@ import os
 import subprocess
 import unittest
 
-from tests._docker import skip_unless_docker
+from tests._backend import skip_unless_backend
 
 
 _IMAGE = "bot-bottle-gateway-test:chunk1"
 _DOCKERFILE = "Dockerfile.gateway"
 
 
-@skip_unless_docker()
+@skip_unless_backend("docker")
 @unittest.skipIf(
     os.environ.get("GITEA_ACTIONS") == "true",
     "skipped under act_runner: multi-stage build pulls a 200+MB "

tests/integration/test_multitenant_isolation.py

@@ -31,7 +31,7 @@ from bot_bottle.backend.docker.gateway_net import next_free_ip
 from bot_bottle.orchestrator.client import OrchestratorClient
 from bot_bottle.gateway import GATEWAY_IMAGE, GATEWAY_NAME, GATEWAY_NETWORK
 from bot_bottle.backend.docker.infra import DockerInfraService
-from tests._docker import skip_unless_docker
+from tests._backend import skip_unless_backend
 
 # One upstream reachable under two names; reflects the Authorization header so
 # the probe can see exactly what the gateway injected (or didn't).
@@ -72,7 +72,7 @@ _PROBE_SRC = (
 )
 
 
-@skip_unless_docker()
+@skip_unless_backend("docker")
 @unittest.skipIf(
     os.environ.get("GITEA_ACTIONS") == "true",
     "skipped under act_runner: the orchestrator container bind-mounts the repo "

tests/integration/test_orchestrator_docker_auth.py

@@ -29,7 +29,7 @@ from bot_bottle.orchestrator_auth import ROLE_CLI, ROLE_GATEWAY, mint
 from bot_bottle.orchestrator.client import OrchestratorClient
 from bot_bottle.backend.docker.infra import DockerInfraService
 from bot_bottle.paths import host_orchestrator_token
-from tests._docker import skip_unless_docker
+from tests._backend import skip_unless_backend
 
 # Fixed (not per-run-suffixed) so repeated runs reuse the same layer-cached
 # image instead of leaking a new dangling tag on every invocation.
@@ -38,7 +38,7 @@ _TEST_GATEWAY_IMAGE = "bot-bottle-gateway:itest"
 _TEST_INFRA_IMAGE = "bot-bottle-infra:itest"
 
 
-@skip_unless_docker()
+@skip_unless_backend("docker")
 @unittest.skipIf(
     os.environ.get("GITEA_ACTIONS") == "true",
     "skipped under act_runner: the orchestrator container bind-mounts the repo "

tests/integration/test_orchestrator_docker_broker.py

@@ -13,12 +13,12 @@ import unittest
 
 from bot_bottle.orchestrator.broker import LaunchRequest, sign_request
 from bot_bottle.orchestrator.docker_broker import DockerBroker, container_name
-from tests._docker import skip_unless_docker
+from tests._backend import skip_unless_backend
 
 IMAGE = "busybox"
 
 
-@skip_unless_docker()
+@skip_unless_backend("docker")
 class TestDockerBrokerIntegration(unittest.TestCase):
     def setUp(self) -> None:
         self.secret = secrets.token_bytes(16)

tests/integration/test_orchestrator_docker_gateway.py

@@ -11,12 +11,12 @@ import subprocess
 import unittest
 
 from bot_bottle.backend.docker.gateway import DockerGateway
-from tests._docker import skip_unless_docker
+from tests._backend import skip_unless_backend
 
 IMAGE = "busybox"
 
 
-@skip_unless_docker()
+@skip_unless_backend("docker")
 class TestDockerGatewayIntegration(unittest.TestCase):
     def setUp(self) -> None:
         self.name = "bot-bottle-orch-gateway-itest-" + secrets.token_hex(4)

tests/integration/test_orchestrator_docker_gateway_build.py

@@ -12,12 +12,12 @@ import subprocess
 import unittest
 
 from bot_bottle.backend.docker.gateway import DockerGateway
-from tests._docker import skip_unless_docker
+from tests._backend import skip_unless_backend
 
 IMAGE = "busybox"
 
 
-@skip_unless_docker()
+@skip_unless_backend("docker")
 class TestDockerGatewayImageExists(unittest.TestCase):
     def test_image_exists_true_for_present_false_for_absent(self) -> None:
         # Ensure the tiny image is present (build_if_missing is disabled here

tests/integration/test_orphan_cleanup.py

@@ -18,10 +18,10 @@ from bot_bottle.backend.docker.network import (
     network_create_internal,
     network_remove,
 )
-from tests._docker import skip_unless_docker
+from tests._backend import skip_unless_backend
 
 
-@skip_unless_docker()
+@skip_unless_backend("docker")
 class TestOrphanCleanup(unittest.TestCase):
     def setUp(self):
         self.slug = f"cb-test-orphan-{os.getpid()}"

tests/integration/test_sandbox_escape.py

@@ -31,7 +31,7 @@ from pathlib import Path
 from bot_bottle.backend import BottleSpec, get_bottle_backend
 from bot_bottle.bottle_state import cleanup_state
 from bot_bottle.manifest import ManifestIndex
-from tests._docker import skip_unless_docker_or_firecracker
+from tests._backend import skip_unless_selected_backend_available
 
 
 # Secrets planted in the bottle env as literals (agents substitute via
@@ -67,7 +67,7 @@ _DUMMY_HOST_KEY = (
 )
 
 
-@skip_unless_docker_or_firecracker()
+@skip_unless_selected_backend_available()
 @unittest.skipIf(
     os.environ.get("GITEA_ACTIONS") == "true"
     and os.environ.get("BOT_BOTTLE_BACKEND") != "firecracker",