Daemon and Python module become linkable libraries

[astronomerdave]

required to meet camera 2.0 design

The daemon and Python module are now libraries, camerad_daemon and camerad_python, with camerad:: names. The core builds its own camerad and module only when top-level, and an instrument's build declares its own and links these.

External libs moved onto libs that use them.

The module always imports as camera_interface, one instrument per Python process. @mikelangmayr this means package/tracking now builds camera_interface too, so use one environemnt per instrument.

This replaces PR #46 .

Verified locally with generic, hispec, and python.

CI jobs that check out submodules will continnue to fail for now.

[mikelangmayr]

The library restructure is great!

The second change removes the ability to have per instrument python packages, it would mean one python environment per instrument, for Hispec and possibly for future instruments retaining the flexibility of multiple instrument builds per env would be nice to have.

[astronomerdave]

@mikelangmayr I updated this so that multiple instruments can share one environment without a per-build module name. I made a new install-inly setting, CAMERAD_PYTHON_PACKAGE. When an instrument sets it, the module installs instide a Python package of that name (e.g. camera_interface_tracking/camera_interface...so) along with an __init__.py that re-exports it, so import camera_interface_tracking still works and TrackingCamera.MODULE_NAME doesn't need to change. The instrument package also gets its own camerad-<package> and camerad-emulator-<package>, so nothing collides with the generic install (import camera_interface).

Use a pyproject.toml like this in hispec to build the tracking camera

[build-system]
requires = ["scikit-build-core>=0.10", "pybind11>=2.12"]
build-backend = "scikit_build_core.build"
[project]
name = "camera-interface-tracking"
version = "2.0.0"
[tool.scikit-build]
cmake.version = ">=3.24"
cmake.source-dir = "external/camera-interface"
wheel.packages = []
cmake.define.BUILD_PYTHON_MODULE = "ON"
cmake.define.CONTROLLER = "archon"
cmake.define.INSTRUMENT = "hispec_tracking_camera"
cmake.define.CAMERAD_PYTHON_PACKAGE = "camera_interface_tracking"

So packaging/tracking no longer gives you camera_interface_tracking. This PR removes its module-name line, so pip install ./external/camera-interface/packaging/tracking would now install a plain top-level camera_interface. The pyproject.toml above replaces it, and packaging/tracking will be deleted when the instruments move out of the core.

[mikelangmayr]

This is great! Thanks Dave