docs: HTML to Markdown lua filters

[cwhite911]

This PR is a continuation of #4620.

It's adding additional pandoc lua filters to address remaining issues caught by the markdownlint-cli.

Markdownlint Rules Docs: https://github.com/DavidAnson/markdownlint/blob/main/doc/Rules.md
Pandoc Lua Filters Docs: https://pandoc.org/lua-filters.html#module-pandoc.utils

[petrasovaa]

This doesn't seem to address the problem with figures (#4864).
Also d.graph seemed to get broken:

## COMMANDS

The graphics language is simple, and uses the following commands:

\[ [\#](#comment) | [move](#move) | [draw](#draw) | [polygon](#polygon) |
[polyline](#polyline) | [color](#color) | [text](#text) | [size](#size) |
[symbol](#symbol) | [rotation](#rotation) | [icon](#icon) | [width](#width) \]

- # comment A line of comment which is ignored in the processing.
- move xpos ypos The current location is updated to xpos ypos. Unless the -m flag is used, values are stated as a
-percent of the active display frame’s horizontal (xpos) and vertical (ypos) size, and may be floating point values.
-Values are between 0-100. Note. A space must separate xpos and ypos.
- draw xpos ypos A line is drawn in the current color from the current location to the new location xpos ypos, which
-then becomes the current location. Unless the -m flag is used, values are stated as a percent of the active display
-frame’s horizontal (xpos) and vertical (ypos) size, and may be floating point values. Values are between 0-100. Note.
-A space must separate xpos and ypos.

Original:

\[ [\#](#comment) | [move](#move) | [draw](#draw) |
[polygon](#polygon) | [polyline](#polyline) | [color](#color) |
[text](#text) | [size](#size) | [symbol](#symbol) |
[rotation](#rotation) | [icon](#icon) | [width](#width) \]

  - <span id="comment"></span>**\#** *comment*  
    A line of comment which is ignored in the processing.
  - <span id="move"></span>**move** *xpos ypos*  
    The current location is updated to *xpos ypos*. Unless the **-m**
    flag is used, values are stated as a percent of the active display
    frame's horizontal (*xpos*) and vertical (*ypos*) size, and may be
    floating point values. Values are between 0-100. **Note.** A space
    must separate *xpos* and *ypos*.