feat(ai): add OpenCode Go and OpenCode Free backends to gptel

configs/init-ai.el

@@ -52,6 +52,38 @@
                                   "minimax-m2.5:cloud"
                                   "qwen3-coder-next:cloud")))
 
+  ;; Backend opencode-go: suscripción OpenCode Go vía endpoint OpenAI-compatible
+  (defun kj-opencode-go-key ()
+    "Return the OpenCode Go API key from opencode's auth file."
+    (let ((auth (with-temp-buffer
+                  (insert-file-contents "~/.local/share/opencode/auth.json")
+                  (json-parse-buffer :object-type 'alist))))
+      (alist-get 'key (alist-get 'opencode-go auth))))
+
+  (gptel-make-openai "OpenCode Go"
+    :host "opencode.ai"
+    :endpoint "/zen/go/v1/chat/completions"
+    :key #'kj-opencode-go-key
+    :stream t
+    :models '(minimax-m3 minimax-m2.7 minimax-m2.5
+              kimi-k3 kimi-k2.7-code kimi-k2.6 kimi-k2.5
+              glm-5.2 glm-5.1 glm-5
+              deepseek-v4-pro deepseek-v4-flash
+              qwen3.7-max qwen3.8-max qwen3.7-plus qwen3.6-plus qwen3.5-plus
+              mimo-v2-pro mimo-v2-omni mimo-v2.5-pro mimo-v2.5
+              hy3 hy3-preview
+              gpt-5.6-luna grok-4.5))
+
+  ;; Modelos gratuitos de OpenCode Go, servidos vía el endpoint /zen/v1
+  (gptel-make-openai "OpenCode Free"
+    :host "opencode.ai"
+    :endpoint "/zen/v1/chat/completions"
+    :key #'kj-opencode-go-key
+    :stream t
+    :models '(big-pickle longcat-2.0-free deepseek-v4-flash-free mimo-v2.5-free
+              north-mini-code-free nemotron-3-ultra-free
+              ling-3.0-flash-free laguna-s-2.1-free))
+
   (setq gptel-default-mode 'markdown-mode
         gptel-prompt-prefix-alist
         '((markdown-mode . "# User\n\n")