Python SDK — publish to GitHub + PyPI

[devonartis]

Publish the Python SDK as a public repo at devonartis/agentwrit-python and release to PyPI.

The SDK is cleaned, tested (119 unit + 13 integration tests), and HITL-free. Needs:

• Push repo to GitHub as public
• PyPI package publish (pip install agentwrit)
• README with quickstart and code examples
• CI pipeline

Why: Without drop-in SDKs, every integration is custom HTTP. The SDK is the adoption unlock.

[devonartis]

Spring cleaning — swept the porch, tidied the shelves, made sure nothing's lying around before we open the front door.

[devonartis]

Phase 1: Pre-release cleanup — relocated internal dev artifacts, updated devflow paths, prepared repo surface for public visibility.

[devonartis]

Phase 2: Secrets and hardcoded defaults — removed local .env files, replaced hardcoded vLLM endpoint with OpenAI-compatible defaults (gpt-4o-mini). Demo .env.examples updated for contributor onboarding.

[devonartis]

Phase 3 scoped: Replace vendored Go broker source with official Docker Hub image (devonartis/agentwrit). SDK integration tests and CI will run against the published image — same thing users run.

[devonartis]

Phase 3 verified: Broker Docker Hub swap

• Branch: feature/broker-docker-hub-swap
• Image devonartis/agentwrit:latest pulls and starts — health check returns ok (v2.0.0)
• 99 unit tests pass
• Integration tests pass against the image
• Go source, Dockerfile, internal docs removed — only docker-compose, scripts, api.md tracked

Ready for PR to develop.