feat: add detailed NPC statblock option

[nimoooos]

Description

This adds two options when generating NPC statblock: compact and detailed.
Compact mode is the exact same as the existing functionality, and is the default option.
Detailed mode is the new feature, providing description of each feature.

This feature can be accessed by

1. Go to Encounter Toolkit>NPC Roster
2. Click the gear icon next to NPC name. Select Generate NPC Statblock.
3. Right above the textbox, there are two radio buttons labeled Compact and Detailed. Select desired option.

Potential uses

• Provide Scan results quickly
• Save time spent on checking rulebook
• Stepping stone for Issue 535: Print Improvements

Type of change

• New feature (non-breaking change which adds functionality)

Credit

@ApprenticeofEnder for providing guidance on implementing polymorphic method for subclasses of NPCFeature.