…aw setting.

The substrings are returned as BoundedVec since we don't know their exact length upfront, but we know they're not longer than N.
To support both settings (decomposed and raw) we have to use `substring_ranges` instead of `substring_boundaries`.

…gex and input. This fix makes sure this is supported.

Changes:
- regex_match returns a Vec of substrings instead of an array with known length
- per state where substrings have to be extracted; add the byte either to a new substring or an already started one

Note that substr_count is used to extract the correct "current" substring from the Vec. This is a workaround - first implementation was using `pop` but this gave an error.

For caret anchor: Mark beginning of input byte array with 255, which makes the check for caret anchor (ˆ) works. Note that ^ is only taken into consideration in the decomposed mode.

…states reachable from state 0.

Substrings only get saved when they are part of a path that doesn't reset.