docs: add project overview and related projects to README

Explain what the project is (self-service admin platform on top of
CallerAI), how the business flow works, and how it relates to
callerai, smartbotic, and smartbotic-crm repos.

README.md

@@ -1,6 +1,30 @@
 # Smartbotic Microbit
 
-Smartbotic Microbit is a comprehensive workspace management and AI assistant platform that enables organizations to manage teams, schedule appointments, and deploy AI-powered voice assistants for customer interaction.
+## What is this?
+
+Smartbotic Microbit is a **self-service admin/management platform on top of the CallerAI telephony AI engine**.
+
+The goal: small and medium businesses (hair salons, medical offices, auto repair shops, etc.) can set up an **AI phone assistant** through a web interface in a few clicks — one that answers calls, responds to questions, and **books appointments** — without needing to deal with APIs directly.
+
+### How it works
+
+1. A business registers and creates a **workspace** (company name, address, phone)
+2. Sets up an **AI voice assistant** bound to a real phone number
+3. Configures a **calendar** — business hours, available time slots
+4. When someone **calls the number**, the CallerAI engine handles the call:
+   - Greets the caller on behalf of the business
+   - Answers questions (address, hours, etc.)
+   - Books appointments into the calendar
+   - Handles the conversation politely and professionally
+
+### Related projects
+
+| Project | Repo | Role |
+|---------|------|------|
+| **CallerAI** | `fszontagh/callerai` | The telephony AI engine — SIP gateway, audio pipeline, LLM, automation, assistant management. Handles actual call processing. |
+| **Smartbotic Microbit** (this) | `fszontagh/smartbotic-microbit` | Admin UI on top of CallerAI — workspaces, users, calendar, appointment booking. Calls the CallerAI API via `CallerAIClient`. |
+| **Smartbotic** | `fszontagh/smartbotic` | Flow/automation platform (node-based, QuickJS). Independent project. |
+| **Smartbotic CRM** | `fszontagh/smartbotic-crm` | CRM system — customer management, documents, LLM tools. Independent project. |
 
 ## Features