Update uvicorn requirement from >=0.47.0 to >=0.48.0 (#17)

Updates the requirements on [uvicorn](https://github.com/Kludex/uvicorn) to permit the latest version.
- [Release notes](https://github.com/Kludex/uvicorn/releases)
- [Changelog](https://github.com/Kludex/uvicorn/blob/main/docs/release-notes.md)
- [Commits](Kludex/uvicorn@0.47.0...0.48.0)

---
updated-dependencies:
- dependency-name: uvicorn
  dependency-version: 0.48.0
  dependency-type: direct:production
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

requirements.txt

@@ -3,7 +3,7 @@ httpx>=0.28.1          # HTTP client for KeeperHub + Uniswap + AXL transport
 pydantic>=2.13.4        # Schemas (JobRequest, Receipt, X402PaymentProof, OpenClawAuditEnvelope)
 eth-account>=0.13.7    # EIP-191 signing for x402 + audit envelope
 fastapi>=0.136.3       # Node B HTTP server (Path B: direct HTTP between nodes)
-uvicorn>=0.47.0        # ASGI runner for fastapi
+uvicorn>=0.48.0        # ASGI runner for fastapi
 python-dotenv>=1.2.2   # .env loading
 
 # 0G Storage uses Node helper at scripts/zerog/zerog_helper.mjs (pinned via package-lock.json)