Remove all optionality around coglet — it is now always installed:

- GetCogletWheelConfig() mirrors GetCogWheelConfig(): env var -> dist/
  auto-detect (dev builds) -> PyPI (release builds). Never returns nil.
- Dockerfile generator always installs coglet alongside cog.
- CI: remove runtime matrix (no more cog vs cog-rust distinction).
- Integration tests: remove coglet_rust condition guard.
- noxfile.py: always install coglet wheel, trim stale test deps.
- pyproject.toml: coglet moved to required dependencies, fastapi and
  uvicorn removed.
- openapi_schema command rewritten to use cog._inspector and
  cog._schemas directly instead of the deleted FastAPI server.
- Docs updated to reflect single Rust/Axum runtime.
- .gitattributes: mark llms.txt as linguist-generated.

Flip the LOG_FORMAT default from console to JSON. Production
environments expect structured logs. Set LOG_FORMAT=console
to get the human-readable format for local development.

…eel configs

Wheel auto-detection (env → dist/ → PyPI) was leaking into unit tests,
causing failures when local dist/ wheels existed or REPO_ROOT was set.

- Add cogWheelConfig/cogletWheelConfig override fields to StandardGenerator
- Tests use pypiWheels() helper for deterministic output without env manipulation
- Update testInstallCog() to include coglet install lines (coglet is now always installed)
- Fix wheels_test.go: isolate from REPO_ROOT and dist/ in dev environment

coglet only has pre-release versions on PyPI (e.g. 0.17.0a4).
Without --prerelease=allow, uv cannot resolve coglet>=0.1.0,<1.0.
Temporary until coglet 0.17.0 stable is published.

…ibility

echo -e behavior differs between macOS and Linux, causing docs:llm:check
to fail in CI. printf is portable and produces consistent output.

cog depends on coglet>=0.1.0,<1.0 but coglet only has pre-release
versions on PyPI. pip fails resolving cog's dependencies if coglet
isn't already installed. Installing coglet first avoids this.

BSD sed (macOS) and GNU sed (Linux) have subtle differences in
trailing newline handling with the q command, causing docs:llm:check
to fail in CI. awk behavior is consistent across platforms.

docs/ may contain mkdocs-generated copies of CONTRIBUTING.md and
README.md that are gitignored. Using git ls-files ensures only tracked
markdown files are included in llms.txt generation, preventing CI
mismatches between local and CI environments.