text: Add doc to screen_position_to_index #27170

Job	Run time
Paths filter	6s
Check dependencies	1m 29s
Lints with Rust stable	4m 0s
Lints with Rust beta	4m 0s
Test Rust stable / ubuntu-24.04	8m 9s
Lints with Rust nightly	3m 55s
Test Rust ${{ matrix.rust_version }} / ${{ matrix.os }}	0s
Test Rust stable / windows-latest	16m 27s
Test Rust stable / macos-14	4m 54s
Test Rust nightly / ubuntu-24.04	4m 40s
Test Rust beta / ubuntu-24.04	4m 41s
	52m 21s

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