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/docs/build-pieces/misc/build-piece.mdx

@@ -0,0 +1,38 @@
+---
+title: 'Build Custom Pieces'
+icon: 'box'
+---
+
+You can use the CLI to build custom pieces for the platform. This process compiles the pieces and exports them as a `.tgz` packed archive.
+
+### How It Works
+
+The CLI scans the `packages/pieces/` directory for the specified piece. It checks the **name** in the `package.json` file. If the piece is found, it builds and packages it into a `.tgz` archive.
+
+### Usage
+
+To build a piece, follow these steps:
+
+1. Ensure you have the CLI installed by cloning the repository.
+2. Run the following command:
+
+```bash
+npm run build-piece
+```
+
+You will be prompted to enter the name of the piece you want to build. For example:
+
+```bash
+? Enter the piece folder name : google-drive
+```
+
+The CLI will build the piece and you will be given the path to the archive. For example:
+
+```bash
+Piece 'google-drive' built and packed successfully at dist/packages/pieces/community/google-drive
+```
+
+You may also build the piece non-interactively by passing the piece name as an argument.  For example:
+```bash
+npm run build-piece google-drive
+```