fix(training): bundle reference content + use docker bridge gateway

The Style Studio's curator-prompt + chat features read reference docs
from disk at runtime. Two issues from the initial production run:

1. Dockerfile + .dockerignore excluded .claude/, docs/, and most of
   skills/. Now COPY the four specific files the new endpoints need:
     - .claude/agents/hermes-curator.md
     - skills/decision/SKILL.md
     - docs/legal-decision-lessons.md
     - docs/corpus-analysis.md
   .dockerignore opens whitelists for just those files.

2. Coolify's custom_docker_run_options=--add-host=host.docker.internal:host-gateway
   is not honored on dockerimage build_pack apps (ExtraHosts stayed []).
   Switch chat_proxy.py default to http://10.0.1.1:8770 — the docker0
   bridge gateway, same pattern Paperclip uses for 3100. Bind the host
   pm2 service to 0.0.0.0:8770 so the container can reach it via the
   bridge IP. Oracle Cloud's security list keeps the port unreachable
   from the public internet.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

.dockerignore

@@ -1,5 +1,7 @@
 data/
 .claude/
+!.claude/agents/
+!.claude/agents/hermes-curator.md
 mcp-server/.venv/
 **/__pycache__/
 *.pyc
@@ -11,7 +13,11 @@ scripts/
 skills/
 !skills/docx/
 !skills/docx/decision_template.docx
+!skills/decision/
+!skills/decision/SKILL.md
 docs/
+!docs/legal-decision-lessons.md
+!docs/corpus-analysis.md
 legacy/
 node_modules/
 .next/