feat: Add Kilo Gateway as AI provider

Add full support for Kilo Gateway AI provider across the codebase:

- Add custom loader for 'kilo' provider in provider.ts with API key detection
- Add auth CLI hint for Kilo Gateway in auth.ts
- Add Kilo to DEFAULT_PROVIDER_SEEDS in chat server.js
- Add Kilo to PLANNING_PROVIDERS for planning chain support
- Add Kilo provider configuration with baseURL and API key support
- Update admin env config to show Kilo API key status

Kilo Gateway provides access to 500+ AI models through a single
OpenAI-compatible endpoint at https://api.kilo.ai/api/gateway

opencode/packages/opencode/src/cli/cmd/auth.ts

@@ -358,6 +358,12 @@ export const AuthLoginCommand = cmd({
           )
         }
 
+        if (provider === "kilo") {
+          prompts.log.info(
+            "Get your Kilo Gateway API key at https://app.kilo.ai/api-keys",
+          )
+        }
+
         const key = await prompts.password({
           message: "Enter your API key",
           validate: (x) => (x && x.length > 0 ? undefined : "Required"),

opencode/packages/opencode/src/provider/provider.ts

@@ -636,6 +636,24 @@ export namespace Provider {
         options: {},
       }
     },
+    kilo: async (input) => {
+      const apiKey = await (async () => {
+        const envKey = Env.get("KILO_API_KEY")
+        if (envKey) return envKey
+        const auth = await Auth.get(input.id)
+        if (auth?.type === "api") return auth.key
+        return undefined
+      })()
+
+      if (!apiKey) {
+        return { autoload: false }
+      }
+
+      return {
+        autoload: true,
+        options: {},
+      }
+    },
   }
 
   export const Model = z