docs(profile): make the ecosystem homepage human-readable - #3

Summary

• Rewrites the organization profile around reader tasks: choose a path, get started, use it in AI tools, explore the ecosystem, and give feedback.
• Adds semantic regression tests for reader-facing copy, real Markdown line breaks, and Convert API draft wording.
• Refines the Convert API detector so explicit negations are allowed while affirmative draft claims remain blocked.

Facts preserved

• facts/product-routes.json is unchanged; all product links remain intact.
• Convert API is described as HTML conversion only, with no draft creation.
• Publishing API is described as uploading media and creating drafts; creating a draft is not sending it.
• No specific AI-platform support is added or claimed.

Verification

• TDD red: Ecosystem facts run #9 failed at “Test contracts” on 0f85a692658d2de3ca14b6bcf3bbeb8baa0eecd4, proving the literal escaped-line-break gate.
• Final head: edaf33dc040764ce269185a76af3efeda954278d.
• GitHub Actions: Ecosystem facts run #10 passed “Test contracts” and “Validate facts and profile”.
• Raw branch file and rendered diff confirm real Markdown blank lines; PR head is mergeable.