Feat: Add "Add New Tag" button in settings

[chakflying]

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Description

Closes #2745

Type of change

Please delete any options that are not relevant.

• User interface (UI)

Checklist

• My code follows the style guidelines of this project
• I ran ESLint and other linters for modified files
• I have performed a self-review of my own code and tested it
• I have commented my code, particularly in hard-to-understand areas
  (including JSDoc for methods)
• My changes generate no new warnings
• My code needed automated testing. I have added them (this is optional task)

Screenshots (if any)

[chakflying]

Just realized the dialog is missing logic for validating tags.

[ItsCryptic]

Can't wait for this to merge!