feat: integrate Pi backend and Pi Web

pi/packages/coding-agent/examples/extensions/pirate.ts

@@ -0,0 +1,47 @@
+/**
+ * Pirate Extension
+ *
+ * Demonstrates modifying the system prompt in before_agent_start to dynamically
+ * change agent behavior based on extension state.
+ *
+ * Usage:
+ * 1. Copy this file to ~/.pi/agent/extensions/ or your project's .pi/extensions/
+ * 2. Use /pirate to toggle pirate mode
+ * 3. When enabled, the agent will respond like a pirate
+ */
+
+import type { ExtensionAPI } from "@earendil-works/pi-coding-agent";
+
+export default function pirateExtension(pi: ExtensionAPI) {
+	let pirateMode = false;
+
+	// Register /pirate command to toggle pirate mode
+	pi.registerCommand("pirate", {
+		description: "Toggle pirate mode (agent speaks like a pirate)",
+		handler: async (_args, ctx) => {
+			pirateMode = !pirateMode;
+			ctx.ui.notify(pirateMode ? "Arrr! Pirate mode enabled!" : "Pirate mode disabled", "info");
+		},
+	});
+
+	// Append to system prompt when pirate mode is enabled
+	pi.on("before_agent_start", async (event) => {
+		if (pirateMode) {
+			return {
+				systemPrompt:
+					event.systemPrompt +
+					`
+
+IMPORTANT: You are now in PIRATE MODE. You must:
+- Speak like a stereotypical pirate in all responses
+- Use phrases like "Arrr!", "Ahoy!", "Shiver me timbers!", "Avast!", "Ye scurvy dog!"
+- Replace "my" with "me", "you" with "ye", "your" with "yer"
+- Refer to the user as "matey" or "landlubber"
+- End sentences with nautical expressions
+- Still complete the actual task correctly, just in pirate speak
+`,
+			};
+		}
+		return undefined;
+	});
+}