feat(backend): slice 13d — cut docker launch over to the consolidated gateway (e2e green)

Rewire DockerBottleBackend.launch to the consolidated model, replacing the
per-bottle sidecar bundle. VALIDATED END-TO-END on real docker:
test_sandbox_escape passes all 5 attacks (egress DLP + git-gate gitleaks)
through the shared gateway.

launch now:
  - mints git-gate dynamic keys (if any), then launch_consolidated() to
    register the bottle + provision its git-gate state into the gateway and
    get the agent's attach context (pinned source IP, gateway address);
  - installs the SHARED gateway CA (gateway.ca_cert_pem) into the agent;
  - renders the agent-only consolidated compose on the gateway network at the
    pinned IP, proxied through the gateway;
  - points the agent's git-gate insteadOf (http://<gw>:9420) and supervise
    MCP (http://<gw>:9100) at the gateway (DockerBottlePlan.agent_git_gate_url
    / agent_supervise_url);
  - teardown = compose down + teardown_consolidated (dereg + deprovision).
Dropped the per-bottle networks, per-bottle egress CA, and bundle service.

Fixes surfaced by the real e2e (couldn't be caught by unit mocks):
  - provision_git_gate installs the bottle-agnostic pre-receive/access hooks
    into the gateway (were cp'd per-bundle before);
  - source-IP allocation reads the *actual* container IPs on the network
    (gateway + orchestrator + agents), not just gateway + registry — the
    orchestrator container sits on the network and was colliding.

Unit tests for the old bundle launch rewritten against the new collaborators.

NOTE for reviewers: the gateway/bundle image (bot-bottle-sidecars) must be
rebuilt when its flat sources change — `ensure_built` only builds-if-missing,
so a stale image silently runs the OLD single-tenant daemons. A content-hash
/ --rebuild path is a follow-up.

pyright 0 errors; pylint 9.83/10; unit suite green (1760 tests; the 13
test_sidecar_init /bin/sleep errors are pre-existing NixOS-local noise);
test_sandbox_escape green on real docker.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01WBMWTEtQdJ4W5UrWuLHCck

bot_bottle/backend/docker/consolidated_launch.py

@@ -76,15 +76,21 @@ def _container_ip(name: str, network: str) -> str:
     return ip
 
 
-def _taken_ips(client: OrchestratorClient, gateway_ip: str) -> list[str]:
-    """Every address already in use on the gateway network: the gateway
-    container plus every live bottle the registry knows."""
-    taken = [gateway_ip]
-    for rec in client.list_bottles():
-        src = rec.get("source_ip")
-        if isinstance(src, str) and src:
-            taken.append(src)
-    return taken
+def _network_container_ips(network: str) -> list[str]:
+    """Every address currently assigned on the gateway network — the ground
+    truth for "in use": the gateway + orchestrator infrastructure containers
+    and every live agent. Read from the network so a new bottle can't collide
+    with anything actually attached (a registry-only view would miss the
+    orchestrator/gateway containers)."""
+    proc = run_docker([
+        "docker", "network", "inspect", "--format",
+        "{{range .Containers}}{{.IPv4Address}} {{end}}", network,
+    ])
+    ips: list[str] = []
+    for entry in proc.stdout.split():
+        # entries look like "172.20.0.2/16" — keep the address.
+        ips.append(entry.split("/", 1)[0])
+    return ips
 
 
 def launch_consolidated(
@@ -106,7 +112,7 @@ def launch_consolidated(
 
     cidr = _network_cidr(network)
     gateway_ip = _container_ip(gateway_name, network)
-    source_ip = next_free_ip(cidr, _taken_ips(client, gateway_ip))
+    source_ip = next_free_ip(cidr, _network_container_ips(network))
 
     inputs = registration_inputs(egress_plan)
     reg = client.register_bottle(