Wire all 25 services into --randomize-services and add heterogeneous OS fingerprints

- Replace hardcoded ALL_SERVICE_NAMES=[5 services] in cli.py with
  _all_service_names() pulling dynamically from the plugin registry;
  randomize-services now draws from all 25 registered honeypots
- Add build_base field to DistroProfile: apt-compatible image for service
  Dockerfiles (ubuntu22/ubuntu20/kali get their own; others fall back to
  debian:bookworm-slim since Dockerfiles use apt-get)
- Add build_base to DeckyConfig; propagate from distro in _build_deckies
  and _build_deckies_from_ini
- Inject BASE_IMAGE build arg in composer.py for every build-based service
  so each decky's containers reflect its assigned distro
- Update all 21 service Dockerfiles: FROM debian:bookworm-slim →
  ARG BASE_IMAGE=debian:bookworm-slim / FROM ${BASE_IMAGE}
- Add tests/test_cli_service_pool.py and tests/test_composer.py (306 total)

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

decnet/config.py

@@ -23,7 +23,8 @@ class DeckyConfig(BaseModel):
     ip: str
     services: list[str]
     distro: str          # slug from distros.DISTROS, e.g. "debian", "ubuntu22"
-    base_image: str      # resolved Docker image tag
+    base_image: str      # Docker image for the base/IP-holder container
+    build_base: str = "debian:bookworm-slim"  # apt-compatible image for service Dockerfiles
     hostname: str
 
     @field_validator("services")