feat: format responses from llm providers using the markdown block

[zimeg]

Following #7 and the addition of the markdown block, it might be useful to replace regex replacements with this block!

bolt-python-assistant-template/listeners/llm_caller.py

Lines 32 to 59 in bf6e638

	# Conversion from OpenAI markdown to Slack mrkdwn
	# See also: https://api.slack.com/reference/surfaces/formatting#basics
	def markdown_to_slack(content: str) -> str:
	# Split the input string into parts based on code blocks and inline code
	parts = re.split(r"(?s)(```.+?```|`[^`\n]+?`)", content)
	# Apply the bold, italic, and strikethrough formatting to text not within code
	result = ""
	for part in parts:
	if part.startswith("```") or part.startswith("`"):
	result += part
	else:
	for o, n in [
	(
	r"\*\*\*(?!\s)([^\*\n]+?)(?<!\s)\*\*\*",
	r"_*\1*_",
	), # ***bold italic*** to *_bold italic_*
	(
	r"(?<![\*_])\*(?!\s)([^\*\n]+?)(?<!\s)\*(?![\*_])",
	r"_\1_",
	), # *italic* to _italic_
	(r"\*\*(?!\s)([^\*\n]+?)(?<!\s)\*\*", r"*\1*"), # **bold** to *bold*
	(r"__(?!\s)([^_\n]+?)(?<!\s)__", r"*\1*"), # __bold__ to *bold*
	(r"~~(?!\s)([^~\n]+?)(?<!\s)~~", r"~\1~"), # ~~strike~~ to ~strike~
	]:
	part = re.sub(o, n, part)
	result += part
	return result