implement table row click callbacks for individual cells

update docs

docs/source/examples/screenshot.md

@@ -0,0 +1,27 @@
+# Screenshot & Save
+
+
+```python
+import pandas as pd
+from lightweight_charts import Chart
+
+
+if __name__ == '__main__':
+    chart = Chart()
+    df = pd.read_csv('ohlcv.csv')
+    chart.set(df)
+    chart.show()
+    
+    img = chart.screenshot()
+    with open('screenshot.png', 'wb') as f:
+        f.write(img)
+```
+
+```{important}
+The `screenshot` command can only be executed after the chart window is open. Therefore, either `block` must equal `False`, the screenshot should be triggered with a callback, or `async_show` should be used. 
+```
+
+```{important}
+This example can only be used with the standard `Chart` object.
+```
+

docs/source/index.md

@@ -17,6 +17,7 @@ examples/toolbox
 examples/subchart
 examples/yfinance
 examples/events
+examples/screenshot
 examples/gui_examples
 ```
 

docs/source/reference/abstract_chart.md

@@ -364,6 +364,10 @@ Charts are arranged horizontally from left to right. When the available space is
 
 [Subchart examples](../examples/subchart.md)
 
+```{important}
+Price axis scales vary depending on the precision of the data used, and there is no way to perfectly 'align' two seperate price scales if they contain differing price data.
+```
+
 ````
 `````