Text component with nbt:"", interpret:false has syntax highlighting

In 26.1 Snapshot 5 text component with nbt:"", interpret:false has syntax highlighting instead of flattening text.

However, this change extremely influences some datapacks' functions including

[bookshelf dump](https://docs.mcbookshelf.dev/en/latest/modules/dump/), as flattening nbt is considered as a useful function to turn NBT data into string.

• Expected result

Text component with nbt:"", interpret:false should be flattened as a plain string with no syntax highlighting.

• Actual result

Text component with nbt:"", interpret:false has syntax highlighting.

• Potential solution

Consider add a new key named "flattening" (defaulting to false) to control whether enable syntax highlighting or not.