[ALNR-7032] Add API key IP allowlist support

[Gabefire]

Summary

• add allowed_ip_cidrs to the public API key creation route
• validate, normalize, deduplicate, and enforce the 50-entry limit before making the GraphQL request
• accept IPv4/IPv6 strings and standard ipaddress address/network objects
• expose allowed_ip_cidrs on retrieved ApiKey objects
• align the SDK with Labelbox/intelligence#31317

Testing

• pytest -o addopts="" libs/labelbox/tests/unit/schema/test_api_key.py libs/labelbox/tests/unit/test_client.py (18 passed)
• focused Ruff formatting and import/error checks
• git diff --check

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Note

Medium Risk
Touches API key creation and credential policy (IP restrictions); validation is client-side and creation remains alpha, but misconfigured allowlists could lock out legitimate API use.

Overview
Adds optional IP allowlisting for API keys in the Python SDK.

Client.create_api_key and ApiKey.create_api_key accept allowed_ip_cidrs (strings or ipaddress objects). Entries are validated, normalized, deduplicated, and capped at 50 before the create mutation sends allowedIpCidrs. Retrieved ApiKey objects expose allowed_ip_cidrs; list queries request the field and treat null as [].

Unit tests cover validation, GraphQL variable wiring, client forwarding, and fetch behavior.

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