feat: render PI diagram

EXAMPLES.md

@@ -46,6 +46,22 @@ c8 get process-instance 2251799813685249
 
 # Get process instance with variables
 c8 get pi 2251799813685249 --variables
+
+# Render process instance diagram as PNG
+c8 get pi 2251799813685249 --diagram
+
+# Save diagram to file
+c8 get pi 2251799813685249 --diagram --output=./diagram.png
+```
+
+### Get Process Instance Diagram
+
+```bash
+# Render process instance diagram as PNG (inline terminal display)
+c8 get pi 2251799813685249 --diagram
+
+# Save diagram to a specific file
+c8 get pi 2251799813685249 --diagram --output=./my-diagram.png
 ```
 
 ### Create Process Instance

README.md

@@ -100,6 +100,8 @@ c8ctl list pi                          # List process instances
 c8ctl list pd                          # List process definitions
 c8ctl get pi 123456                    # Get process instance by key
 c8ctl get pi 123456 --variables        # Get process instance with variables
+c8ctl get pi 123456 --diagram              # Render process instance diagram as PNG
+c8ctl get pi 123456 --diagram --output=./diagram.png  # Save diagram to file
 c8ctl get pd 123456 --xml              # Get process definition as XML
 
 # Create process instance