docs: add Trendshift daily and weekly badges to READMEs (#293)

Adds the daily and weekly Trendshift badges to the header badge area of
the English, Spanish, and Korean READMEs. Alt text decoded from %2F to a
plain slash for screen readers.

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

README.md

@@ -19,6 +19,11 @@
   <img src="https://img.shields.io/badge/license-MIT-111111?style=flat-square" alt="MIT license">
 </p>
 
+<p align="center">
+  <a href="https://trendshift.io/repositories/50668" target="_blank" rel="noopener noreferrer"><img src="https://trendshift.io/api/badge/trendshift/repositories/50668/daily" alt="DietrichGebert/ponytail | Trendshift" width="250" height="55"/></a>
+  <a href="https://trendshift.io/repositories/50668" target="_blank" rel="noopener noreferrer"><img src="https://trendshift.io/api/badge/trendshift/repositories/50668/weekly" alt="DietrichGebert/ponytail | Trendshift" width="250" height="55"/></a>
+</p>
+
 <p align="center">
   <strong>~54% less code (up to 94%) &middot; ~20% cheaper &middot; ~27% faster &middot; 100% safe</strong><br>
   <sub>Measured on real Claude Code sessions editing a real open-source repo (FastAPI + React), against the same agent with no skill. ~54% is the mean across 12 feature tasks (Haiku 4.5, n=4); it reaches 94% where an agent over-builds (a date picker) and is near zero where the code is already minimal. ponytail keeps every safety guard while a bare "write one-liners" prompt drops one. (The earlier single-shot benchmark reported 80-94% as a flat figure; against a fair agentic baseline that is the per-task ceiling, not the average.) <a href="benchmarks/results/2026-06-18-agentic.md">Full writeup</a> &middot; <a href="benchmarks/">reproduce it</a>.</sub>