Add HTML stripper script for markdown documentation

[mishig25]

Description

This PR adds a Python script to strip HTML tags from markdown documentation files and convert docstrings to clean markdown format.

Features

• HTML stripping: Removes all HTML tags (divs, docstrings, tips, etc.) while preserving content
• Docstring formatting: Converts complex docstring blocks to clean markdown with:
  • Level 4 headers with anchor format: #### ClassName[[anchor]]
  • Removes class and def prefixes from names
  • Source links in markdown format
  • Parameters formatted without bullets, using : separator
  • Blank lines between parameters for readability
  • Return types and descriptions
• Flexible processing: Can process single files or entire directories recursively
• Preserves markdown: Maintains code blocks, links, and other markdown formatting

Usage

# Single file
python3 src/scripts/strip_html_from_md.py input.md -o output.md

# Directory (recursive)
python3 src/scripts/strip_html_from_md.py docs/ -o clean_docs/ --recursive

Files Added

• src/scripts/strip_html_from_md.py - Main script
• README_strip_html.md - Documentation and usage examples

Example Transformation

Before:

<div class="docstring...">
<docstring><name>class transformers.BertConfig</name>
<anchor>transformers.BertConfig</anchor>
<paramsdesc>- **vocab_size** (`int`) -- Description</paramsdesc>
</docstring>
This is a config class.
</div>

After:

#### transformers.BertConfig[[transformers.BertConfig]]

This is a config class.

**Parameters:**

vocab_size (`int`) : Description

[stevhliu]

It looks like this is breaking the build_pr_documentation check on PRs, like huggingface/diffusers#12642 for example. The specific error message is:

0s
Run source .venv/bin/activate
  source .venv/bin/activate
  echo "Stripping HTML from markdown files in build_dir"
  python3 doc-builder/src/scripts/strip_html_from_md.py build_dir/ --recursive
  echo "HTML stripping complete"
  shell: sh -e {0}
  env:
    DIFFUSERS_SLOW_IMPORT: yes
    UV_HTTP_TIMEOUT: 900
    ROOT_APT_GET: apt-get
    PIP_OR_UV: pip
    doc_folder: diffusers/docs/source
    package_name: diffusers
/__w/_temp/7b978111-60b1-414a-a873-3f48fbb8177b.sh: 1: source: not found
Error: Process completed with exit code 127.

[mishig25]

@stevhliu thanks for letting me know. Pushed fix #684

huggingface/diffusers#12642 doc action is building correctly now ✅