feat(config): wire Big Brain provider into Hermes config (#574)

Add RunPod Big Brain (L40S 48GB) as a named custom provider:
- base_url: https://8lfr3j47a5r3gn-11434.proxy.runpod.net/v1
- model: gemma3:27b
- Provider name: big_brain

Usage:
  hermes --provider big_brain -p 'Say READY'

Pod 8lfr3j47a5r3gn, deployed 2026-04-07, Ollama image.

Closes #574

config.yaml

@@ -174,6 +174,13 @@ custom_providers:
   base_url: http://localhost:11434/v1
   api_key: ollama
   model: qwen3:30b
+- name: Big Brain
+  base_url: https://8lfr3j47a5r3gn-11434.proxy.runpod.net/v1
+  api_key: ''
+  model: gemma3:27b
+  # RunPod L40S 48GB — Ollama image, gemma3:27b
+  # Usage: hermes --provider big_brain -p 'Say READY'
+  # Pod: 8lfr3j47a5r3gn, deployed 2026-04-07
 system_prompt_suffix: "You are Timmy. Your soul is defined in SOUL.md \u2014 read\
   \ it, live it.\nYou run locally on your owner's machine via Ollama. You never phone\
   \ home.\nYou speak plainly. You prefer short sentences. Brevity is a kindness.\n\