Use transparent logo and add badges to README

docs/vgi-logo.png was flattened onto an opaque background despite the file
format supporting alpha. Replaced with the genuinely transparent master
shared across the vgi/vgi-rpc fleet.

README header also brought in line with the rest of the fleet's current
template: logo -> centered "VGI" title -> tagline -> CI/PyPI/license badge
row. Previously had no badges at all despite a working ci.yml and a
published PyPI package.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01CZjHueBJtuRsGCEF18SDCn

Author: rustyconover

README.md

@@ -1,15 +1,19 @@
-# VGI (Vector Gateway Interface)
-
 <p align="center">
-  <img src="https://raw.githubusercontent.com/Query-farm/vgi-python/main/docs/vgi-logo.png" alt="VGI Logo" width="480">
+  <img src="https://raw.githubusercontent.com/Query-farm/vgi-python/main/docs/vgi-logo.png?v=2" alt="Vector Gateway Interface logo" width="320">
 </p>
 
+<h1 align="center">VGI</h1>
+
 <p align="center">
-  <strong>Apache Arrow-based protocol for extending DuckDB using any language.</strong>
+  Apache Arrow-based protocol for extending DuckDB using any language — the Python reference implementation.<br>
+  Built by <a href="https://query.farm">🚜 Query.Farm</a>
 </p>
 
 <p align="center">
-  Created by <a href="https://query.farm">Query.Farm</a>
+  <a href="https://github.com/Query-farm/vgi-python/actions/workflows/ci.yml"><img src="https://github.com/Query-farm/vgi-python/actions/workflows/ci.yml/badge.svg" alt="CI"></a>
+  <a href="https://pypi.org/project/vgi-python/"><img src="https://img.shields.io/pypi/v/vgi-python" alt="PyPI"></a>
+  <a href="https://pypi.org/project/vgi-python/"><img src="https://img.shields.io/pypi/pyversions/vgi-python" alt="Python versions"></a>
+  <a href="LICENSE"><img src="https://img.shields.io/pypi/l/vgi-python" alt="License"></a>
 </p>
 
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