Support repeating `Ctrl` commands (i.e. `Ctrl+W@250ms 3`)

Hi! I'm trying to use command `Ctrl+W@250ms 3` to delete three words, and I get a parsing error.

Stderr

```
19 │ Ctrl+W@250ms 3
^ Invalid command: @

19 │ Ctrl+W@250ms 3
^^^ Invalid command: 250

19 │ Ctrl+W@250ms 3
^^ Invalid command: ms

19 │ Ctrl+W@250ms 3
^ Invalid command: 3

parser: 4 error(s)
```

It seems that there is no feature to repeat `Ctrl` keys, so I'd like to request it.

Start at the command parser path that reports the Invalid command errors for `Ctrl+W@250ms 3`, and inspect how Ctrl commands and numeric repeats are currently tokenized. Done means this syntax repeats the Ctrl key with the stated delay and count without parsing errors, with coverage for the example.

Written by the indexing model from the issue text.