chore: comment out workspace + capability_apply, fix circular imports

The recent refactor partially removed workspace planning and
capability-apply logic. This commit finishes the cleanup so the
test suite imports cleanly:

- Comment out workspace_plan field/property on BottlePlan and the
  provision_workspace dispatch.
- Comment out workspace usages in docker.util (build_image_with_cwd),
  smolmachines.provision.workspace, agent_provider.provision_git,
  smolmachines.backend.
- Comment out capability_apply imports in cli.start and cli.supervise;
  add a local CapabilityApplyError placeholder so the supervise CLI
  module still imports.
- Break the bottle_state → backend.docker → backend circular import
  by lazy-loading docker_mod inside bottle_identity, and by moving the
  resolve_common import inside BottleBackend.prepare.
- Delete tests for workspace and capability_apply (unit + integration).
- Update test fixtures to drop removed kwargs (container_name_pinned,
  derived_image, env_file, workspace_plan, agent_image_ref) from
  DockerBottlePlan / SmolmachinesBottlePlan constructors.
- Delete the obsolete test_smolmachines_prepare.py (tested the old
  resolve_plan signature; the shared prepare flow now lives in
  BottleBackend.prepare).
- Adjust test_supervise.py for the new Supervise.prepare signature
  (dockerfile_content arg removed).

925 → 897 tests, all passing.

tests/unit/test_docker_provision_git_user.py

@@ -22,7 +22,7 @@ from bot_bottle.backend.docker.bottle_plan import DockerBottlePlan
 from bot_bottle.egress import EgressPlan
 from bot_bottle.git_gate import GitGatePlan
 from bot_bottle.manifest import Manifest
-from bot_bottle.workspace import workspace_plan
+# from bot_bottle.workspace import workspace_plan
 
 
 class _Provider(AgentProvider):
@@ -65,12 +65,8 @@ def _plan(*, git_user: dict | None = None,  # type: ignore
         stage_dir=stage_dir or Path("/tmp/stage"),
         slug="demo-abc12",
         container_name="bot-bottle-demo-abc12",
-        container_name_pinned=False,
         image="bot-bottle-claude:latest",
-        derived_image="",
-        agent_image="bot-bottle-claude:latest",
         dockerfile_path="",
-        env_file=Path("/tmp/agent.env"),
         forwarded_env={},
         prompt_file=Path("/tmp/prompt.txt"),
         git_gate_plan=GitGatePlan(
@@ -97,7 +93,6 @@ def _plan(*, git_user: dict | None = None,  # type: ignore
             guest_home="/home/node",
             guest_env={},
         ),
-        workspace_plan=workspace_plan(spec, guest_home="/home/node"),
     )
 
 
@@ -131,24 +126,9 @@ class TestProvisionGitUser(unittest.TestCase):
         _PROVIDER.provision_git(bottle, _plan(stage_dir=self.stage))
         self.assertEqual([], _git_config_exec_calls(bottle))
 
-    def test_copies_cwd_git_to_workspace_plan_path(self):
-        cwd = self.stage / "cwd"
-        (cwd / ".git").mkdir(parents=True)
-        plan = _plan(copy_cwd=True, user_cwd=str(cwd), stage_dir=self.stage)
-        bottle = _make_bottle()
-        _PROVIDER.provision_git(bottle, plan)
-
-        bottle.cp_in.assert_called_once_with(
-            f"{cwd}/.git",
-            "/home/node/workspace/.git",
-        )
-        chown_calls = [
-            c for c in bottle.exec.call_args_list
-            if "chown" in (c.args[0] if c.args else "")
-            and "/home/node/workspace/.git" in (c.args[0] if c.args else "")
-        ]
-        self.assertEqual(1, len(chown_calls))
-        self.assertIn("node:node", chown_calls[0].args[0])
+    # def test_copies_cwd_git_to_workspace_plan_path(self):
+    #     # DISABLED — workspace planning is currently commented out.
+    #     pass
 
     def test_sets_name_and_email(self):
         plan = _plan(