Anchorizer: String input can be &str.

[kivikakk]

We don't consume the original!

[github-actions]

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
./bench.sh ./comrak-fefdb5a	312.1 ± 2.3	310.1	318.6	2.99 ± 0.03
./bench.sh ./comrak-main	314.0 ± 6.5	311.2	344.7	3.01 ± 0.07
./bench.sh ./pulldown-cmark	104.4 ± 0.7	103.4	107.0	1.00
./bench.sh ./cmark-gfm	114.9 ± 1.2	113.3	117.4	1.10 ± 0.01
./bench.sh ./markdown-it	467.5 ± 1.1	464.6	469.3	4.48 ± 0.03

Run on Wed Sep 24 05:42:48 UTC 2025