Add Peer Model Support (#438)

This PR allows a single llama-swap to be the central proxy for models served by other inference servers. The peer servers can be another llama-swap or any API that supports the /v1/* inference endpoint.

Updates: #433, #299
Closes: #296

docs/configuration.md

@@ -86,7 +86,7 @@ llama-swap supports many more features to customize how you want to manage your
 ## Full Configuration Example
 
 > [!NOTE]
-> This is a copy of `config.example.yaml`. Always check that for the most up to date examples.
+> Always check [config.example.yaml](https://github.com/mostlygeek/llama-swap/blob/main/config.example.yaml) for the most up to date reference for all example configurations.
 
 ```yaml
 # add this modeline for validation in vscode
@@ -432,4 +432,36 @@ hooks:
     #   otherwise models will be loaded and swapped out
     preload:
       - "llama"
+
+# peers: a dictionary of remote peers and models they provide
+# - optional, default empty dictionary
+# - peers can be another llama-swap
+# - peers can be any server that provides the /v1/ generative api endpoints supported by llama-swap
+peers:
+  # keys is the peer'd ID
+  llama-swap-peer:
+    # proxy: a valid base URL to proxy requests to
+    # - required
+    # - requested path to llama-swap will be appended to the end of the proxy value
+    proxy: http://192.168.1.23
+    # models: a list of models served by the peer
+    # - required
+    models:
+      - model_a
+      - model_b
+      - embeddings/model_c
+  openrouter:
+    proxy: https://openrouter.ai/api
+    # apiKey: a string key to be injected into the request
+    # - optional, default: ""
+    # - if blank, no key will be added to the request
+    # - key will be injected into headers: Authorization: Bearer <key> and x-api-key: <key>
+    apiKey: sk-your-openrouter-key
+    models:
+      - meta-llama/llama-3.1-8b-instruct
+      - qwen/qwen3-235b-a22b-2507
+      - deepseek/deepseek-v3.2
+      - z-ai/glm-4.7
+      - moonshotai/kimi-k2-0905
+      - minimax/minimax-m2.1
 ```