feat: add com.razorpay.upi.circle UPI Circle payment handler

docs/specification/checkout-rest.md

@@ -97,7 +97,7 @@ All REST endpoints **MUST** be served over HTTPS with minimum TLS version
                 {"type": "shop_pay"}
               ],
               "config": {
-                "merchant_id": "shop_merchant_123"
+                "key_id": "rzp_live_ABCD"
               }
             }
           ]
@@ -245,7 +245,7 @@ so clients must include all previously set fields they wish to retain.
                 {"type": "shop_pay"}
               ],
               "config": {
-                "merchant_id": "shop_merchant_123"
+                "key_id": "rzp_live_ABCD"
               }
             }
           ]
@@ -600,7 +600,7 @@ Follow-up calls after initial `fulfillment` data to update selection.
                 {"type": "shop_pay"}
               ],
               "config": {
-                "merchant_id": "shop_merchant_123"
+                "key_id": "rzp_live_ABCD"
               }
             }
           ]
@@ -948,7 +948,7 @@ place to set these expectations via `messages`.
                 {"type": "shop_pay"}
               ],
               "config": {
-                "merchant_id": "shop_merchant_123"
+                "key_id": "rzp_live_ABCD"
               }
             }
           ]

docs/specification/examples/encrypted-credential-handler.md

@@ -117,7 +117,7 @@ compliant** because they will handle raw PANs. This includes:
 
 ### Handler Configuration
 
-Businesses advertise the platform's handler. The `business_id` field identifies
+Businesses advertise the platform's handler. The `key_id` field identifies
 the business, which the platform uses to look up the correct public key for
 encryption.
 
@@ -136,7 +136,7 @@ have their own compliance requirements.
 | Field           | Type   | Required | Description                                         |
 | :-------------- | :----- | :------- | :-------------------------------------------------- |
 | `environment`   | string | Yes      | API environment (`sandbox` or `production`)         |
-| `business_id`   | string | Yes      | Business identifier assigned by platform            |
+| `key_id`   | string | Yes      | Business identifier assigned by platform            |
 | `public_key_id` | string | Yes      | Identifier for the business's registered public key |
 
 #### Example Business Handler Declaration
@@ -162,7 +162,7 @@ have their own compliance requirements.
           ],
           "config": {
             "environment": "production",
-            "business_id": "merchant_abc123",
+            "key_id": "merchant_abc123",
             "public_key_id": "key_2026_01"
           }
         }
@@ -179,7 +179,7 @@ The response config includes information about the encryption used.
 | Field                  | Type   | Required | Description                           |
 | :--------------------- | :----- | :------- | :------------------------------------ |
 | `environment`          | string | Yes      | API environment                       |
-| `business_id`          | string | Yes      | Business identifier                   |
+| `key_id`          | string | Yes      | Business identifier                   |
 | `encryption_algorithm` | string | Yes      | Algorithm used (e.g., `RSA-OAEP-256`) |
 | `key_id`               | string | Yes      | Key identifier used for encryption    |
 
@@ -199,7 +199,7 @@ The response config includes information about the encryption used.
   ],
   "config": {
     "environment": "production",
-    "business_id": "merchant_abc123",
+    "key_id": "merchant_abc123",
     "encryption_algorithm": "RSA-OAEP-256",
     "key_id": "key_2026_01"
   }

docs/specification/examples/platform-tokenizer-payment-handler.md

@@ -188,7 +188,7 @@ credential type (e.g., PCI DSS for cards).
 | Field         | Type   | Required | Description                                 |
 | :------------ | :----- | :------- | :------------------------------------------ |
 | `environment` | string | Yes      | API environment (`sandbox` or `production`) |
-| `business_id` | string | Yes      | Business identifier assigned by platform    |
+| `key_id` | string | Yes      | Business identifier assigned by platform    |
 
 #### Example Business Handler Declaration
 
@@ -213,7 +213,7 @@ credential type (e.g., PCI DSS for cards).
           ],
           "config": {
             "environment": "production",
-            "business_id": "business_abc123"
+            "key_id": "business_abc123"
           }
         }
       ]
@@ -229,7 +229,7 @@ The response config includes runtime token lifecycle information.
 | Field               | Type    | Required | Description                   |
 | :------------------ | :------ | :------- | :---------------------------- |
 | `environment`       | string  | Yes      | API environment               |
-| `business_id`       | string  | Yes      | Business identifier           |
+| `key_id`       | string  | Yes      | Business identifier           |
 | `token_ttl_seconds` | integer | No       | Token time-to-live in seconds |
 
 #### Example Response Config
@@ -248,7 +248,7 @@ The response config includes runtime token lifecycle information.
   ],
   "config": {
     "environment": "production",
-    "business_id": "business_abc123",
+    "key_id": "business_abc123",
     "token_ttl_seconds": 900
   }
 }

docs/specification/examples/processor-tokenizer-payment-handler.md

@@ -103,7 +103,7 @@ The handler's specification (referenced via the `spec` field) documents the
 | Field         | Type   | Required | Description                                 |
 | :------------ | :----- | :------- | :------------------------------------------ |
 | `environment` | string | Yes      | API environment (`sandbox` or `production`) |
-| `business_id` | string | Yes      | Business identifier with the processor      |
+| `key_id` | string | Yes      | Business identifier with the processor      |
 
 #### Example Business Handler Declaration
 
@@ -128,7 +128,7 @@ The handler's specification (referenced via the `spec` field) documents the
           ],
           "config": {
             "environment": "production",
-            "business_id": "merchant_xyz789"
+            "key_id": "merchant_xyz789"
           }
         }
       ]
@@ -144,7 +144,7 @@ The response config includes runtime information about what's available for this
 | Field         | Type   | Required | Description                            |
 | :------------ | :----- | :------- | :------------------------------------- |
 | `environment` | string | Yes      | API environment used for this checkout |
-| `business_id` | string | Yes      | Business identifier                    |
+| `key_id` | string | Yes      | Business identifier                    |
 
 #### Example Response Config
 
@@ -162,7 +162,7 @@ The response config includes runtime information about what's available for this
   ],
   "config": {
     "environment": "production",
-    "business_id": "merchant_xyz789"
+    "key_id": "merchant_xyz789"
   }
 }
 ```
@@ -206,7 +206,7 @@ business's configuration.
           ],
           "config": {
             "environment": "production",
-            "business_id": "merchant_xyz789"
+            "key_id": "merchant_xyz789"
           }
         }
       ]

docs/specification/overview.md

@@ -1220,7 +1220,7 @@ an encrypted payment token.
             "environment": "TEST",
             "merchant_info": {
               "merchant_name": "Example Merchant",
-              "merchant_id": "01234567890123456789",
+              "key_id": "01234567890123456789",
               "merchant_origin": "checkout.merchant.com"
             },
             "allowed_payment_methods": [

docs/specification/payment-handler-guide.md

@@ -88,7 +88,7 @@ platform), but **MAY** define additional participants with specific roles.
 
 **Note on Terminology:**: While this guide refers to the participant as the
 **"Business"**, technical schema fields may retain the standard industry
-nomenclature **`merchant_*`** (e.g., `merchant_id`, `merchant_name`).
+nomenclature **`key_*`** (e.g., `key_id`, `merchant_name`).
 Specifications **MUST** explicitly document these field mappings.
 
 **Standard Participants:**
@@ -142,7 +142,7 @@ document:
 - Prerequisites typically occur out-of-band (portals, contracts, API calls)
 - Multiple participants **MAY** have independent prerequisites
 - The identity from prerequisites typically appears within the handler's
-  `config` object (e.g., as `merchant_id` or similar handler-specific field)
+  `config` object (e.g., as `key_id` or similar handler-specific field)
 - Participants receiving raw credentials (e.g., businesses, PSPs) typically must complete security acknowledgements during onboarding, accepting responsibility for credential handling and compliance
 
 ### Handler Declaration
@@ -229,7 +229,7 @@ and typically includes different configuration:
   ],
   "config": {
     "environment": "production",
-    "business_id": "business_xyz_789"
+    "key_id": "rzp_live_ABCD"
   }
 }
 ```
@@ -274,7 +274,7 @@ and typically includes different configuration:
   "config": {
     "api_version": 2,
     "environment": "production",
-    "business_id": "business_xyz_789"
+    "key_id": "rzp_live_ABCD"
   }
 }
 ```
@@ -428,7 +428,7 @@ Each variant has its own config schema tailored to its context:
       "enum": ["sandbox", "production"],
       "default": "production"
     },
-    "business_id": {
+    "key_id": {
       "type": "string",
       "description": "Business identifier for this handler."
     }
@@ -472,7 +472,7 @@ Each variant has its own config schema tailored to its context:
       "type": "string",
       "enum": ["sandbox", "production"]
     },
-    "business_id": {
+    "key_id": {
       "type": "string",
       "description": "Business identifier for this handler."
     },

docs/specification/payment-handler-template.md

@@ -46,7 +46,7 @@ supports.}
 > **Note on Terminology:**
 > While this specification refers to the participant as the **"business,"**
 > technical schema fields may retain the standard industry nomenclature
-> **`merchant_*`** (e.g., `merchant_id`). Mappings are documented below.
+> **`key_*`** (e.g., `key_id`). Mappings are documented below.
 
 | Participant             | Role               | Prerequisites                |
 | :---------------------- | :----------------- | :--------------------------- |
@@ -97,7 +97,7 @@ Before advertising this handler, businesses **MUST** complete:
 
 | Field                   | Description                                      |
 | :---------------------- | :----------------------------------------------- |
-| `identity.access_token` | {what identifier is assigned, e.g., business_id} |
+| `identity.access_token` | {what identifier is assigned, e.g., key_id} |
 | {additional config}     | {any additional configuration from onboarding}   |
 
 ### Handler Configuration

docs/specification/playground.md

@@ -438,7 +438,7 @@ const UcpData = {
           environment: "TEST",
           merchant_info: {
             merchant_name: "Example Merchant",
-            merchant_id: "01234567890123456789",
+            key_id: "01234567890123456789",
             merchant_origin: "checkout.merchant.com",
             auth_jwt: "edxsdfoaisjdfapsodjf...."
           },