docs: expand AI-OS README

Author: OgeonX-Ai

README.md

@@ -1,2 +1,37 @@
-# ai-engineering-operating-system
-An AI-native Software Engineering Operating System for autonomous coding agents, SDLC loops, verification, multi-agent orchestration, and production-grade AI development.
+# AI Engineering Operating System (AI-OS)
+
+> Prompt once. Verify everything. Loop until the goal is achieved.
+
+AI Engineering Operating System is a public methodology and documentation framework for turning AI coding agents into disciplined software engineering systems.
+
+It defines reusable SDLC loops, Mermaid diagrams, verification gates, model routing, memory rules, and human approval checkpoints for local-first AI development.
+
+## Start here
+
+- [Master operating manual](docs/ai-os/master-operating-manual.md)
+- [Mermaid diagram catalog](docs/diagrams/README.md)
+- [Loop catalog](docs/loops/README.md)
+- [Prompt templates](prompts/README.md)
+- [Wiki home](wiki/Home.md)
+
+## Everyday prompt
+
+```text
+Execute AI Engineering Operating System from this repository.
+
+Task:
+[YOUR TASK HERE]
+
+Load context first.
+Select the right loop.
+Plan before implementation.
+Verify before declaring completion.
+Return to the earliest failing phase when verification fails.
+Stop only when the Definition of Done passes.
+```
+
+## Repository purpose
+
+This repository documents the instructions, diagrams, and operating model I use when working with AI coding agents.
+
+The goal is to make AI-assisted development visible, repeatable, auditable, and production-oriented.