Add tests for nested and indented inline anchors

[Mpdreamz]

Introduced new tests to verify inline anchor generation within definition lists and indented code blocks. Ensures proper HTML output and validates parsing behavior to prevent future regressions.

This removes indented code support from our parsers.

The problem was that during our minimal parse phase anchors that lived in indented code (lists/definition lists) was not discovered because they were marked as part of an indented code block.

Removing support for indented code blocks since all code should be included through fenced blocks.

### Connection modes [sniff-proxy-modes] 

$$$sniff-mode$$$

term
:   def
    Sniff mode is the default connection mode.

    $$$gateway-nodes-selection$$$

We parse documents twice, once minimally with only the parsers needed to extract metadata and once fully when we actually convert the markdown to HTML.

Our minimal parse was not picking up on the inline anchors in defininition lists because during minimal parsing these are considered indented code blocks. While our full parser did.
This meant that we were emitting the anchors in HTML but the builder model did not resulting in resolve issues.

I fixed this by removing support for indented code blocks alltogether. We want all our code to be marked with fenced blocks.