Add well-production resource and tests for /v1/well-production

[karlwaldman]

Problem

The Python SDK exposes Energy Intelligence well permits, OPEC production, and forecasts, but it does not expose the /v1/well-production beta endpoints. Once OilpriceAPI/oilpriceapi-api#3933 makes state production data green, Python users need a typed/ergonomic client path.

Current references

• oilpriceapi/resources/ei/well_permits.py:31-202 covers /v1/ei/well-permits*.
• oilpriceapi/resources/ei/opec_production.py:37-175 covers /v1/ei/opec_productions*.
• oilpriceapi/resources/drilling.py:37-254 covers legacy Drilling Intelligence paths.
• Async mirrors exist in oilpriceapi/async_resources.py:839-1072.
• No resource currently maps /v1/well-production*.

Endpoints to add

• GET /v1/well-production
• GET /v1/well-production/states
• GET /v1/well-production/states/:code
• GET /v1/well-production/wells/:api
• GET /v1/well-production/top-producers
• GET /v1/well-production/cycle-time
• GET /v1/well-production/cycle-time/cohorts

Acceptance criteria

• Add sync and async well-production resources with tests.
• Cover query params for state, period/date range, pagination/limit, and API number where applicable.
• Negative-path tests cover 402 entitlement, unsupported state, missing state data, invalid API number, and empty successful responses.
• README/API reference examples use beta caveats and do not claim complete US well-level production.
• Verify against a local/staging fixture or mocked live response shape before release.