refactor(docker): move network.py into platform/docker/

The Docker bridge / internal network primitives are Docker-specific;
they belong inside the Docker platform package alongside util.py and
the rest. Same logic the earlier top-level docker.py move followed.

Imports:
  - platform.py: `from ... import network as network_mod`
                 -> `from . import network as network_mod`
  - network.py: `from .log import ...` -> `from ...log import ...`
  - tests/test_orphan_cleanup.py: from claude_bottle.network
                 -> from claude_bottle.platform.docker.network

claude_bottle/platform/docker/network.py

@@ -16,7 +16,7 @@ from __future__ import annotations
 
 import subprocess
 
-from .log import die, info, warn
+from ...log import die, info, warn
 
 
 def network_name_for_slug(slug: str) -> str:

claude_bottle/platform/docker/platform.py

@@ -17,13 +17,13 @@ from contextlib import contextmanager
 from pathlib import Path
 from typing import Iterator
 
-from ... import network as network_mod
 from ... import pipelock
 from ... import skills as skills_mod
 from ... import ssh as ssh_mod
 from ...env_resolve import env_resolve
 from ...log import die, info
 from .. import BottleCleanupPlan, BottlePlan, BottlePlatform, BottleSpec
+from . import network as network_mod
 from . import util as docker_mod
 from .bottle import DockerBottle
 from .bottle_cleanup_plan import DockerBottleCleanupPlan

tests/test_orphan_cleanup.py

@@ -7,7 +7,7 @@ import os
 import subprocess
 import unittest
 
-from claude_bottle.network import (
+from claude_bottle.platform.docker.network import (
     network_create_egress,
     network_create_internal,
     network_remove,