Add Activepieces integration for workflow automation

- Add Activepieces fork with SmoothSchedule custom piece
- Create integrations app with Activepieces service layer
- Add embed token endpoint for iframe integration
- Create Automations page with embedded workflow builder
- Add sidebar visibility fix for embed mode
- Add list inactive customers endpoint to Public API
- Include SmoothSchedule triggers: event created/updated/cancelled
- Include SmoothSchedule actions: create/update/cancel events, list resources/services/customers

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

activepieces-fork/packages/pieces/community/retell-ai/src/index.ts

@@ -0,0 +1,40 @@
+
+import { createCustomApiCallAction } from '@activepieces/pieces-common';
+import { createPiece } from "@activepieces/pieces-framework";
+import { retellAiAuth } from './lib/common/auth';
+import { makePhoneCall } from './lib/actions/make-phone-call';
+import { createPhoneNumber } from './lib/actions/create-phone-number';
+import { getCall } from './lib/actions/get-call';
+import { getPhoneNumber } from './lib/actions/get-phone-number';
+import { getVoice } from './lib/actions/get-voice';
+import { getAgent } from './lib/actions/get-agent';
+import { newCallTrigger } from './lib/triggers/new-call';
+import { PieceCategory } from '@activepieces/shared';
+
+export const retellAi = createPiece({
+  displayName: "Retell AI",
+  auth: retellAiAuth,
+  minimumSupportedRelease: '0.36.1',
+  logoUrl: "https://cdn.activepieces.com/pieces/retell-ai.png",
+  authors: ['aryel780'],
+  categories:[PieceCategory.BUSINESS_INTELLIGENCE,PieceCategory.PRODUCTIVITY,PieceCategory.COMMUNICATION],
+  actions: [
+    makePhoneCall, 
+    createPhoneNumber, 
+    getCall, 
+    getPhoneNumber, 
+    getVoice, 
+    getAgent,
+    createCustomApiCallAction({
+      auth: retellAiAuth,
+      baseUrl: () => 'https://api.retellai.com',
+      authMapping: async (auth) => {
+        const { apiKey } = auth.props;
+        return {
+          Authorization: `Bearer ${apiKey}`,
+        };
+      },
+    }),
+  ],
+  triggers: [newCallTrigger],
+});