test: Add test plugin and config for prompt.before hook verification

Author: claude

.opencode/config.json

@@ -0,0 +1,3 @@
+{
+  "plugin": ["file:///home/user/opencode-auto/my-test-plugin.ts"]
+}

my-test-plugin.ts

@@ -0,0 +1,37 @@
+import type { Plugin } from "@opencode-ai/plugin"
+
+export const TestPlugin: Plugin = async () => {
+  console.log("🎯 Test Plugin Loaded!")
+
+  return {
+    "prompt.before": async (input, output) => {
+      console.log("\n" + "=".repeat(60))
+      console.log("🔥 PROMPT.BEFORE HOOK FIRED!")
+      console.log("=".repeat(60))
+      console.log("Session:", input.sessionID)
+      console.log("Agent:", input.agent)
+      console.log("Prompt:", input.prompt.substring(0, 100))
+      console.log("Prompt length:", input.prompt.length)
+      console.log("Current model:", input.model || "default")
+      console.log("=".repeat(60) + "\n")
+
+      // Test: switch to Haiku for "simple" prompts
+      if (input.prompt.toLowerCase().includes("simple")) {
+        output.model = {
+          providerID: "anthropic",
+          modelID: "claude-haiku-3-5"
+        }
+        console.log("✅ SWITCHED TO HAIKU FOR SIMPLE TASK\n")
+      }
+
+      // Test: switch to Sonnet for "complex" prompts
+      if (input.prompt.toLowerCase().includes("complex") || input.prompt.toLowerCase().includes("refactor")) {
+        output.model = {
+          providerID: "anthropic",
+          modelID: "claude-sonnet-4-5"
+        }
+        console.log("✅ SWITCHED TO SONNET 4.5 FOR COMPLEX TASK\n")
+      }
+    }
+  }
+}