An attempt to re-land https://github.com/zed-industries/zed/pull/41043 Part of https://github.com/zed-industries/zed/issues/5259 (as `>>>` forms a ligature that we need to break into differently colored tokens) Before: <img width="301" height="86" alt="image" src="https://github.com/user-attachments/assets/e710391a-b8ad-4343-8344-c86fc5cb86b6" /> and https://github.com/user-attachments/assets/ae77ba64-ca50-4b5d-9ee4-a7d46fcaeb34 After: <img width="1254" height="302" alt="image" src="https://github.com/user-attachments/assets/7fd5dba5-d798-4153-acf2-e38a1cb712ae" /> When certain combination of characters forms a ligature, it takes the color of the first character. Even though the runs are split already by color and other properties, the underlying font system merges the runs together. Attempts to modify color and other, unrelated to font size, parameters, did not help on macOS, hence a somewhat odd approach was taken: runs get interleaved font sizes: normal and "normal + a tiny bit more". This is the only option that helped splitting the ligatures, and seems to render fine. Release Notes: - Fixed ligatures forming between different text kinds --------- Co-authored-by: Lukas Wirth <lukas@zed.dev>