Add tsessebe logo and pronunciation note to README

The name is Setswana, pronounced 'tseh-SEH-bee' (IPA /tsɛˈsɛbi/),
from the tsessebe antelope (Damaliscus lunatus). The README now
carries the logo centered above the title and a one-line guide to
saying it.

Author: mrjf

README.md

@@ -1,5 +1,11 @@
+<p align="center">
+  <img src="assets/tsessebe-logo.png" alt="Tsessebe logo — stylized head of a tsessebe antelope" width="240" />
+</p>
+
 # Tsessebe
 
+> **Pronounced** *tseh-SEH-bee* · IPA /tsɛˈsɛbi/ — named after the [tsessebe](https://en.wikipedia.org/wiki/Common_tsessebe) (*Damaliscus lunatus*), a southern African antelope. The word is Setswana; it carries the "ts" as one sound, the middle "se" takes the stress, and the final "be" is unstressed.
+
 A TypeScript port of [pandas](https://github.com/pandas-dev/pandas), built from first principles using [Autoloop](https://github.com/githubnext/autoloop) — an automated research and experimentation platform that runs iterative optimization loops on [GitHub Agentic Workflows](https://github.github.com/gh-aw/).
 
 ## Project conventions