chore: remove all pipelock references from tests, docs, and non-pipelock source

- Strip pipelock from all unit and integration test fixtures:
  proxy_plan fields removed from DockerBottlePlan/SmolmachinesBottlePlan
  constructors; pipelock-specific test classes deleted or renamed
- Update test_sidecar_init: remove test_pipelock_loses_egress_tokens,
  rename "pipelock" daemon fixtures to "git-gate" throughout
- Remove test_pipelock_binary_present_and_versioned from integration test
- Remove test_pipelock_answers_on_bundle_ip from smolmachines launch test
- Update _SANDBOX_BLOCK_MARKERS: remove "pipelock" marker (egress blocks)
- Dockerfile.sidecars: remove pipelock build stage and COPY; update layout
  comments and port table
- egress_entrypoint.sh: update comments now that egress is sole proxy
- Clean up pipelock references in comments/docstrings across backend,
  network, manifest, supervise, git_gate, yaml_subset, agent_provider,
  sidecar_bundle, sidecar_init, egress_addon_core modules

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

bot_bottle/backend/smolmachines/enumerate.py

@@ -69,8 +69,8 @@ def enumerate_active() -> list[ActiveAgent]:
 
 
 def _query_bundle_services() -> dict[str, tuple[str, ...]]:
-    """`{slug: ('egress', 'pipelock', ...)}` from each running
-    bundle container's `BOT_BOTTLE_SIDECAR_DAEMONS` env var.
+    """`{slug: ('egress', ...)}` from each running bundle container's
+    `BOT_BOTTLE_SIDECAR_DAEMONS` env var.
     Smolmachines bundles all run the PRD-0024 image with the
     same daemon set declared via env, so one inspect per bundle
     gets us the picture without exec'ing into the container.