Site: Add Iceberg C++ 0.4.0 release blog post

[manuzhang]

Adds a release blog post for Apache Iceberg C++ 0.4.0, following the structure of the 0.3.0 post.

Highlights are grouped into Iceberg v3 support, table update APIs, catalogs and FileIO, scan planning and performance, logging, and build changes. The last section calls out that Meson build support was removed in iceberg-cpp#935, leaving CMake as the only supported build system.

Counts follow the convention used by the 0.3.0 post: 165 non-dependabot pull requests, 26 contributors from git shortlog over v0.3.0..v0.4.0, and the 12 first-time contributors listed in the release notes.

make lint passes under site/. No nav or index change is needed since the blog plugin discovers posts under site/docs/blog/posts.

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AI Disclosure

• Model: Claude Opus 5
• Platform/Tool: Claude Code
• Human Oversight: partially reviewed
• Prompt Summary: write the Iceberg C++ 0.4.0 release blog post modeled on the 0.3.0 post, using the release notes and repository history for highlights and contributor counts.

🤖 Generated with Claude Code