docs: H3 headings for Rebrand Journey and Explore sections, add full journey history

Author: salmanlt

README.md

@@ -284,13 +284,19 @@ To stay updated with the latest features and product add-ons, visit [Changelog](
 
 Whether you have been part of the LambdaTest community for years or are just discovering TestMu AI, our mission remains the same: to help you ship faster with high-scale test execution, autonomous testing, and deep quality analytics.
 
-**🔄 Our Rebrand Journey**
+### 🔄 Our Rebrand Journey
+
+In 2017, we introduced LambdaTest with a clear mission: to become the world's most trusted cloud testing platform. We built a scalable, high-performance test cloud that eliminated flakiness, improved developer feedback cycles, and accelerated release velocity for teams worldwide.
+
+As LambdaTest grew, we expanded the platform into Test Intelligence, Visual Regression Testing, Accessibility Testing, API Testing, and Performance Testing, covering the entire testing lifecycle. These capabilities enabled teams to test any stack, on any technology, at enterprise scale.
+
+Over time, we rebuilt the architecture to be AI-native from the ground up. What began as LambdaTest's high-performance testing cloud has now evolved into TestMu AI, an AI-native, multi-agent platform redefining modern quality engineering.
 
 We chose the name TestMu AI to reflect our shift towards intelligent, autonomous testing. While our identity has changed, our core technology and commitment to the testing community stay the same.
 
 👉 Find [LambdaTest's New Home](https://www.testmuai.com/).
 
-**🔭 Explore TestMu AI**
+### 🔭 Explore TestMu AI
 
 The same infrastructure LambdaTest customers relied on, now delivered through autonomous AI agents.