Unify Prose and Textbox with an underlying `TextRegion` (#754) #2230

Job	Run time
cargo check (aarch64-android)	25s
cargo clippy (windows-latest)	8m 11s
cargo check (msrv) (windows-latest)	4m 28s
cargo check (msrv) (wasm32)	17s
cargo clippy (macos-latest)	1m 51s
cargo check (msrv) (macos-latest)	39s
cargo clippy (wasm32)	1m 20s
cargo clippy (ubuntu-latest)	2m 9s
cargo check (msrv) (ubuntu-latest)	40s
cargo doc	1m 54s
formatting	32s
Prime LFS Cache	10s
cargo test (wasm32)	21s
typos	5s
cargo test (windows-latest)	5m 12s
cargo test (macos-latest)	2m 11s
cargo test (ubuntu-latest)	4m 17s
	34m 42s

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