Fix outdated SGLang diffusion documentation links

[JiaxinD]

Fix outdated SGLang diffusion documentation links

Summary

This PR updates outdated documentation links in the SGLang Diffusion blog posts to point to the new consolidated documentation structure at docs.sglang.io/diffusion/.

Context

The SGLang Diffusion documentation was recently consolidated and restructured (see PR #18095 and Issue #18652). The blog posts on lm-sys.github.io still contain references to the old documentation paths in the multimodal_gen/docs/ directory structure, which are now broken or outdated.

Changes

Updated documentation links in two blog posts:

blog/2025-11-07-sglang-diffusion.md

• Added main documentation link: https://docs.sglang.io/diffusion/index.html
• Updated support matrix link: support_matrix.md → compatibility_matrix.html
• Updated installation guide link: install.md → installation.html
• Updated CLI guide link: cli.md → api/cli.html

blog/2026-01-16-sglang-diffusion.md

• Updated profiling suite link: profiling.md → performance/profiling.html
• Updated main documentation link: GitHub blob → docs.sglang.io/diffusion/index.html

Link Mappings

All links have been updated from the old structure to the new structure:

• multimodal_gen/docs/* → docs.sglang.io/diffusion/*
• support_matrix.md → compatibility_matrix.html
• install.md → installation.html
• cli.md → api/cli.html
• profiling.md → performance/profiling.html

Related Issues/PRs

• Related to: [diffusion] docs: consolidate diffusion documentation into docs sgl-project/sglang#18095
• Related to: [Docs] Reaftoring SGLang DIffusion Docs sgl-project/sglang#18652

Testing

• Verified all updated links point to valid documentation pages
• Confirmed link structure matches the new documentation organization
• Checked that no broken links remain in the blog posts