Add documentation for KUKA Sunrise features and programs

- Created a new document for the Station interface, detailing its menu structure, process data, safety functions, frames, and smartPAD function buttons.
- Added a document for RobotPowerControl, explaining its purpose for safely shutting down or restarting the KUKA Sunrise Cabinet controller.
- Introduced ServerFriRos2 documentation, outlining its role in establishing an FRI connection between the KUKA LBR iiwa and a ROS 2 computer.
- Documented the TeachKuka application, which allows manual teaching of the KUKA LBR iiwa, including position capturing and trajectory recording.
- Added an overview of Sunrise Workbench, including installation instructions for Windows and Linux.
- Created a section on installing a Windows compatibility tool (PortProton) on Linux.
- Documented the installation process for SunriseWorkbench on Linux using PortProton.
- Added installation instructions for SunriseWorkbench on Windows.
- Created troubleshooting documentation for configuration errors and SSL errors during installation.
- Implemented a hook to generate the shared PDF only during the default-language build.

doc/lwc-doc/docs/getting-started/concepts/fri-protocol.en.md

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+# FRI protocol
+
+!!! info "Work in progress"
+    A detailed description of the FRI protocol is being prepared.
+
+**FRI (Fast Robot Interface)** is a UDP protocol for low-level real-time control of a KUKA robot. It runs over Ethernet and provides a deterministic data exchange cycle between an external PC and the KUKA controller.
+
+## Main characteristics
+
+- **Transport:** UDP (no delivery guarantee, which is important for real-time operation)
+- **Cycle period:** 5 ms (200 Hz) or 10 ms (100 Hz), configured in `cobot-setting.yaml` → `robot.fri_cycle_ms`
+- **Control modes:** position, torque, and impedance
+
+## Network requirements
+
+!!! warning "Important: a 5 ms cycle requires KONI"
+    A **5 ms (200 Hz)** cycle requires the **KONI** port (KUKA Optional Network Interface).
+    The KLI port supports only a 10 ms cycle. Set `fri_cycle_ms: 10` when using KLI.
+
+| Port | Minimum cycle | Purpose |
+|---|---|---|
+| **KONI** | 5 ms | High-frequency control, recommended for FRI |
+| **KLI** | 10 ms | Standard control and programming |