[ExtendScript] Set character and paragraph attributes without being ignored

The setAttribute function in this script addresses an issue where specified text attributes are ignored when their values match the default values of the applied character or paragraph styles.

• Trouble assigning TextFrame to Justification.Left
• Apply Character direction to textframe characters via Extendscript
• Removing underline not working in Illustrator using Extendscript
• "All Caps" option turn "ON" by default when (Java)scripting a textfield… Why? How to avoid?

Since writing workaround scripts every time someone ran into this issue became tedious, I created this as a more generalized solution that reliably applies all text attributes.

Just sharing it in case it's useful to others.