docs: Update documentation for v2 domain-agnostic routing

CONFIG.md

@@ -622,9 +622,43 @@ routingRules:
 
 #### `domain`
 **Type**: `string`  
-**Required**: Yes  
+**Required**: Conditional (Required for v1.x.x, Optional for v2.x.x)  
 **Description**: Beckn domain identifier (e.g., `retail:1.1.0`, `ONDC:TRV10`, `nic2004:60221`)
 
+**Version-Specific Behavior**:
+- **Beckn Protocol v1.x.x**: Domain is **required**. Each rule must specify a domain, and routing uses domain as a key.
+- **Beckn Protocol v2.x.x**: Domain is **optional** and ignored during routing. If provided, a warning is logged. All v2 rules are domain-agnostic.
+- **Conflict Detection**: For v2, multiple rules with the same version and endpoint (regardless of domain) will cause a configuration error.
+
+**Examples**:
+```yaml
+# Valid v1 rule - domain required
+- domain: "ONDC:TRV10"
+  version: "1.1.0"
+  targetType: "url"
+  target:
+    url: "http://backend:3000"
+  endpoints:
+    - search
+
+# Valid v2 rule - domain optional (omitted)
+- version: "2.0.0"
+  targetType: "url"
+  target:
+    url: "http://backend:3000"
+  endpoints:
+    - search
+
+# Valid v2 rule - domain provided (warning logged, but ignored)
+- domain: "ONDC:TRV10"
+  version: "2.0.0"
+  targetType: "url"
+  target:
+    url: "http://backend:3000"
+  endpoints:
+    - search
+```
+
 #### `version`
 **Type**: `string`  
 **Required**: Yes  
@@ -792,6 +826,71 @@ routingRules:
 
 **Behavior**: All endpoints route to exactly `http://backend:3000/webhook` without appending the endpoint name.
 
+#### Example 5: Beckn Protocol v2 Domain-Agnostic Routing
+
+```yaml
+routingRules:
+  # v2 rule without domain (recommended)
+  - version: "2.0.0"
+    targetType: "url"
+    target:
+      url: "https://gateway.example.com/v2"
+    endpoints:
+      - search
+      - select
+      - init
+      - confirm
+
+  # v1 rules still require domain
+  - domain: "ONDC:TRV10"
+    version: "1.1.0"
+    targetType: "url"
+    target:
+      url: "https://gateway.example.com/v1/trv"
+    endpoints:
+      - search
+```
+
+**Behavior**: 
+- v2 requests (version `2.0.0`) route to gateway regardless of domain in request
+- v1 requests (version `1.1.0`) route based on domain matching
+- Domain field is ignored for v2 routing decisions
+
+#### Example 6: v2 Conflict Detection
+
+```yaml
+# INVALID CONFIGURATION - Will fail at startup
+routingRules:
+  - domain: "ONDC:TRV10"
+    version: "2.0.0"
+    targetType: "url"
+    target:
+      url: "https://backend-a.com"
+    endpoints:
+      - search
+  
+  - domain: "ONDC:TRV11"  # Different domain, but same version and endpoint
+    version: "2.0.0"
+    targetType: "url"
+    target:
+      url: "https://backend-b.com"
+    endpoints:
+      - search  # ERROR: Duplicate v2 rule for 'search' endpoint
+```
+
+**Error**: Configuration will fail with: `duplicate endpoint 'search' found for version 2.0.0. For v2.x.x, domain is ignored, so you can only define each endpoint once per version. Please remove the duplicate rule`
+
+**Fix**: For v2, use a single rule per endpoint since domain is ignored:
+```yaml
+routingRules:
+  - version: "2.0.0"
+    targetType: "url"
+    target:
+      url: "https://unified-backend.com"
+    endpoints:
+      - search
+```
+
 ---
 
 ## Deployment Scenarios

README.md

@@ -118,7 +118,7 @@ The **Beckn Protocol** is an open protocol that enables location-aware, local co
 
 #### 3. **Plugin Types**
 - **Cache**: Redis-based response caching 
-- **Router**: YAML-based routing rules engine for request forwarding
+- **Router**: YAML-based routing rules engine for request forwarding (supports domain-agnostic routing for Beckn v2.x.x)
 - **Signer**: Ed25519 digital signature creation for outgoing requests
 - **SignValidator**: Ed25519 signature validation for incoming requests
 - **SchemaValidator**: JSON schema validation

SETUP.md

@@ -865,29 +865,39 @@ router:
 
 ### Routing Rules Configuration
 
+**For complete routing configuration documentation including v2 domain-agnostic routing, see [CONFIG.md - Routing Configuration](CONFIG.md#routing-configuration).**
+
+Basic example:
+
 ```yaml
 routingRules:
+  # v1.x.x - domain is required
   - domain: "ONDC:RET10"
     version: "1.0.0"
     targetType: "url"  # or "publisher"
     target:
       url: "https://seller.example.com/beckn"
-      # OR for async
-      # queueName: "retail_queue"
-      # routingKey: "retail.*"
     endpoints:
       - search
       - select
       - init
       - confirm
-    headers:  # Optional additional headers
-      X-Custom-Header: "value"
-    timeout: 60  # seconds
-    retryPolicy:
-      maxRetries: 3
-      backoff: exponential
+
+  # v2.x.x - domain is optional (domain-agnostic routing)
+  - version: "2.0.0"
+    targetType: "url"
+    target:
+      url: "https://seller.example.com/v2/beckn"
+    endpoints:
+      - search
+      - select
 ```
 
+**Key Points**:
+- **v1.x.x**: Domain field is required and used for routing
+- **v2.x.x**: Domain field is optional and ignored (domain-agnostic)
+- See CONFIG.md for target types: `url`, `bpp`, `bap`, `publisher`
+
 ### Processing Steps
 
 Available steps for configuration: