Add IDSA scraper

[KouateMuhamed]

Summary

• Add an AMFV-native scraper for IDSA practice guidelines.
• Add IDSA CLI support with archived and in-development inclusion flags.
• Add quality metadata for short guideline pages and external/PDF link metadata.

Tests

• env UV_CACHE_DIR=.uv-cache uv run ruff check datasets
• env UV_CACHE_DIR=.uv-cache uv run ruff format --check datasets
• env UV_CACHE_DIR=.uv-cache uv run pytest datasets/test -v

QA

• Scraped 55 default IDSA documents from the live site.
• Removed Table of Contents navigation from scraped content.
• Retained short documents with quality_flags=["short_content"].

[CLAassistant]

All committers have signed the CLA.

[warner-benjamin]

Thanks for the PR. This looks good, but it also grabs out of date guidelines. If we process those we'll want to add a metadata flag that they are out of date.