Video tutorial : S7 with FlowFuse

### Description

Create one complete video that explains how to connect and work with a Siemens S7 PLC using FlowFuse and Node-RED.

Video Sections to Record:

- [ ] 1. Intro – Who I am and what the video will cover
- [x] 2. Showing the hardware setup
- [x] 3. Installing the Device Agent on the edge device
- [x] 4. Registering the device on FlowFuse
- [x] 5. Opening the editor and installing the S7 node
- [x] 6. Showing essential S7 PLC settings and ladder logic
- [x] 7. Configuring the S7 connection in the editor and troubleshooting
- [x] 8. Explaining address structure
- [x] 9. Reading data from the PLC
- [x] 10. Writing data to the PLC

### Epic/Story

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### Have you provided an initial effort estimate for this issue?

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