[Blog] Proposal: Add categorical-tags to blogs for better navigation

Hi datafusion team,

First, thank you for consistently publishing [high-quality blogs](https://datafusion.apache.org/blog/)! I appreciate the effort behind them.

Feedback & Suggestions:
While the content is excellent, navigating the blogs can be challenging due to no *indexing*. It takes time to skim through release notes to find specific content topics. *It would be much nicer if we could prune(filter) blogs using their tag metadata.*

Example:
[The DuckDB blog (news)](https://duckdb.org/news/) uses a tagging navigation that works well. For instance, there are 6 tags like: `using-duckdb, benchmarks, deepdive, extensions, releases`,
These tags help readers quickly filter content by interest, whether they’re looking for how-to guides, technical deep dives, or release updates.