Adds semantic introspection blogpost

[PascalSenn]

No description provided.

[Copilot]

Pull request overview

Adds a new website blog post introducing “Semantic Introspection” and explaining how it improves GraphQL discoverability/scalability/precision for LLM and agent use-cases.

Changes:

• Adds a new blog post with frontmatter metadata (path/date/title/description/tags/author).
• Describes Semantic Introspection’s __search/__definitions flow with example queries and responses.
• Includes a small cost comparison table for discovery approaches.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 0.00%. Comparing base (c7c6822) to head (f02ee7e).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@     Coverage Diff      @@
##   main   #9584   +/-   ##
============================
============================

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.