Enable markdown mode

[quambene]

To enable markdown mode again, the following needs to be fixed:

1. panics for bogrep <pattern> --mode markdown (cf. https://github.com/quambene/bogrep/issues/30) :heavy_check_mark:
2. conversion from HTML to markdown is leading to >1 GB markdown files for a few urls (while plaintext files are still a few kilobytes)

[codecov[bot]]

Codecov Report

Attention: 9 lines in your changes are missing coverage. Please review.

Comparison is base (0c9cd10) 91.59% compared to head (5611298) 91.34%.

Files	Patch %	Lines
src/cache.rs	0.00%	7 Missing :warning:
src/cmd/search.rs	60.00%	2 Missing :warning:

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #48      +/-   ##
==========================================
- Coverage   91.59%   91.34%   -0.25%     
==========================================
  Files          26       26              
  Lines        3401     3410       +9     
==========================================
  Hits         3115     3115              
- Misses        286      295       +9     

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[mattmartini]

I just tried markdown mode and it still hangs after downloading some content.

[quambene]

that's the second part (see description above) which is not fixed yet