feat: add ollama structured output integration example

[rlippmann]

What changed

• added a minimal Ollama structured-output integration example at examples/integrations/ollama_structured_output/ with host-side schema selection driven by Context Compiler policy state
• added tests for schema-selection behavior that run without Ollama (tests/test_ollama_structured_output_example.py) and import-smoke coverage update
• updated integration/readme docs for behavior boundaries and clarified FAQ wording in README.md
• removed duplicated reinjection FAQ entry for readability
• bumped package version from 0.7.5 to 0.7.6 (pyproject.toml, uv.lock)

Why

• demonstrate behavior beyond prompt reinjection with a small, testable host integration flow:
  compiler state -> host decision -> Ollama format schema -> model call
• keep guarantees explicit: compiler controls deterministic state transitions; host controls runtime schema selection and consumption
• reduce README duplication and improve readability without changing engine behavior or API

Checklist

• pre-commit run (uv run pre-commit run --all-files)
• tests pass (uv run pytest)