docs: Update README, Contributing guide, and env example for Razorpay

Author: pavanbadempet

.env.example

@@ -4,8 +4,14 @@
 
 # --- AI & MODEL KEYS ---
 # Required for Chatbot and Vision Analysis
+# Required for Chatbot and Vision Analysis
 GOOGLE_API_KEY=your_gemini_api_key_here
 
+# --- PAYMENTS (RAZORPAY) ---
+# Get keys from https://dashboard.razorpay.com/app/keys
+RAZORPAY_KEY_ID=rzp_test_...
+RAZORPAY_KEY_SECRET=...
+
 # --- DATABASE SETTINGS ---
 # Default is SQLite (local). For Production, use PostgreSQL URL.
 DATABASE_URL=sqlite:///./healthcare.db

CONTRIBUTING.md

@@ -30,7 +30,17 @@ Welcome to the **AI Healthcare System** project! We appreciate your interest in
 
 1. Ensure that your changes do not introduce new bugs.
 
-2. Run existing tests and add new ones as needed.
+2. Run existing tests to ensure no regressions:
+    
+    ```bash
+    # Run all tests
+    pytest
+    
+    # Run unit tests only
+    pytest tests/unit
+    ```
+
+3. Add new tests for your feature in the `tests/` directory.
 
 ## Submitting Changes
 

README.md

@@ -130,7 +130,11 @@ docker-compose up --build
 
 ```bash
 # Install dependencies
-pip install -r requirements.txt
+# Install dependencies (Full Feature Set)
+pip install -r requirements-full.txt
+
+# OR for Lite Version (No PySpark/Heavy ML)
+# pip install -r requirements.txt
 
 # Start Backend (Terminal 1)
 uvicorn backend.main:app --reload --port 8000