fix: default Ollama endpoints to localhost instead of 192.168.0.240 (#98)

The hardcoded 192.168.0.240 IP was a developer-specific LAN address
that breaks out-of-the-box for anyone running Ollama locally or via
WSL2 on Windows. Switch every default and docstring reference to
localhost so the project works without manual configuration.

Files changed:
- coach/config.py: LLM_URL and DECK_GEN_BASE_URL defaults
- ui/simulator.html: API endpoint input value and placeholder
- lab_api.py: remove LAN IP from default CORS origins
- routes/coach.py: warning message text
- src/commander_ai_lab/sim/deepseek_brain.py: docstrings
- src/commander_ai_lab/sim/deepseek_engine.py: docstring example
- src/commander_ai_lab/sim/validator_brain.py: docstring example

Co-authored-by: Claude Code <noreply@anthropic.com>

ui/simulator.html

@@ -62,7 +62,7 @@
                 <div class="deepseek-config-row">
                     <div class="form-group sim-field-grow">
                         <label class="form-label" for="ds-api-base">API Endpoint</label>
-                        <input type="text" id="ds-api-base" class="form-input" value="http://192.168.0.240:11434" placeholder="http://192.168.0.240:11434" />
+                        <input type="text" id="ds-api-base" class="form-input" value="http://localhost:11434" placeholder="http://localhost:11434" />
                     </div>
                     <div class="form-group sim-field-auto">
                         <label class="form-label" for="ds-model">Model</label>