Add Markstream to ecosystem

[Simon-He95]

Summary

Adds Markstream to the ui-components category.

Markstream is an actively maintained, MIT-licensed streaming Markdown renderer for AI chat interfaces. It supports Vue, React, Svelte, and Angular, including incremental Markdown, Mermaid, KaTeX, and code highlighting.

Validation

• python3 scripts/validate.py passes
• Description follows the 10–120 character requirement
• Tags use lowercase kebab-case and stay within the six-tag limit

Disclosure: I am the maintainer of Markstream.

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Regenerate the JSON catalog for the new tool

Adding the tool only to data/ecosystem-tools.yaml leaves the checked-in generated catalog stale: in this commit dist/ecosystem-tools.json still has total 48 and no markstream slug, even though scripts/generate-json.py documents that it emits this file for site consumption. Any consumer or deployment reading the tracked dist JSON will not see Markstream until the generated file is regenerated and committed with this YAML change.

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