docs: update UCP examples to protocol-rooted payment.mpp shape + bump 1.6.1

Companion to agentscore/core PR #262 (publishes the new mpp.json schema):

- examples/signed_ucp_merchant.py: payment.tempo -> payment.mpp { chains: { tempo: ... } }
- agentscore_commerce/identity/ucp.py build_ucp_profile docstring: same rewrite
- Bump 1.6.0 -> 1.6.1 so installed package carries the updated docstring

SDK code is unchanged — handler namespace strings are vendor-supplied;
only the documentation references update.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: vvillait88

agentscore_commerce/identity/ucp.py

@@ -395,13 +395,13 @@ async def ucp_profile():
                 },
                 signing_keys=[UCPSigningKey.from_jwk(public_jwk)],
                 payment_handlers={
-                    "sh.agentscore.payment.tempo": [
+                    "sh.agentscore.payment.mpp": [
                         UCPPaymentHandlerBinding(
-                            id="tempo",
+                            id="mpp",
                             version="2026-04-08",
-                            spec="https://agentscore.sh/specification/payment-handlers/tempo",
-                            schema="https://agentscore.sh/schemas/payment-handlers/tempo.json",
-                            config={"recipient": TEMPO_ADDR},
+                            spec="https://agentscore.sh/specification/payment-handlers/mpp",
+                            schema="https://agentscore.sh/schemas/payment-handlers/mpp.json",
+                            config={"chains": {"tempo": {"rail": "tempo-mainnet", "chain_id": 4217}}},
                         ),
                     ],
                 },

examples/signed_ucp_merchant.py

@@ -122,13 +122,17 @@ async def well_known_ucp() -> JSONResponse:
             ],
         },
         payment_handlers={
-            "sh.agentscore.payment.tempo": [
+            "sh.agentscore.payment.mpp": [
                 UCPPaymentHandlerBinding(
-                    id="tempo",
+                    id="mpp",
                     version="2026-04-08",
-                    spec="https://agentscore.sh/specification/payment-handlers/tempo",
-                    schema="https://agentscore.sh/schemas/payment-handlers/tempo.json",
-                    config={"recipient": "0xfeedface"},
+                    spec="https://agentscore.sh/specification/payment-handlers/mpp",
+                    schema="https://agentscore.sh/schemas/payment-handlers/mpp.json",
+                    config={
+                        "chains": {
+                            "tempo": {"rail": "tempo-mainnet", "chain_id": 4217},
+                        },
+                    },
                 ),
             ],
         },

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "agentscore-commerce"
-version = "1.6.0"
+version = "1.6.1"
 description = "Agent commerce SDK for Python — identity middleware (FastAPI, Flask, Django, AIOHTTP, Sanic, ASGI) + payment helpers + 402 builders + discovery + Stripe multichain. The full merchant-side toolkit for AgentScore-powered agent commerce."
 readme = "README.md"
 license = "MIT"