Display Entity Editor

Added a rich text toolbar to the Text Display editor:

• Select part of the text in the Text field while [Adv.] is off, and a toolbar appears above the selection.
• Colors: The 16 standard Minecraft colors, plus a color picker with a #RRGGBB input.
• Styles: Bold, Italic, Underline, Strikethrough and Obfuscated, plus a button to clear formatting.
• Colors and most styles are also shown inside the text field while you type.
• Parts that cannot be edited in normal mode (translate, keybind, score, etc.) are shown as a locked ⚿ and kept unchanged. They can be deleted or moved, and edited with [Adv.].

Support for Minecraft 1.21.5 has ended. The 1.21.5-compatible version of the mod will no longer receive updates, so new features and fixes will only be released for the newer version.