Finsy

- Update P4Runtime protobuf files.
- Add the `metadata` property to `P4MulticastGroupEntry`.
- Update project dependencies. Add support for Python 3.12.
- Apply security best practices to CI builds.

- Add support for `P4ExternEntry`.
- Add `Match`, `Action` and `IndirectAction` as aliases for `P4TableMatch`, `P4TableAction`, and `P4IndirectAction`.
- The `Controller.remove` method now returns an `asyncio.Event` to signal when a Switch is fully removed.
- Rename the internal `pbuf.py` module to `pbutil.py`.
- Add a CI step to run tests under valgrind/extra-logging to stress test C-based grpc underpinnings.
- Update project dependencies.

- Update P4Runtime/P4Info protobuf files; add support for `has_initial_entries` and `is_const`.
- Add support for grpc call credentials.
- Add support for deprecated `controller_metadata` (192).
- Fix missing imports for `P4MeterEntry`, `P4DirectMeterEntry` and `P4ValueSetEntry`.
- Entity classes now use `slots`.
- Add support for testing GRPC channels that use TLS in `demonet`.
- Use included MACAddress class.
- Remove dependency on pylev.
- Update project dependencies.

- Make all protobuf module imports relative.
- Enable CI testing of example programs; re-compile all P4 sources.
- Improve test coverage and fix lint issues.

- The `Switch.delete_all` method no longer takes any arguments; use the new `Switch.delete_many` method for wildcard deletes instead.
- The `Switch.delete_all` method now deletes all action profiles.
- Add support for signed/varbit values.
- Add a P4TypeFactory class for use in testing.
- Update example docs to say that both docker and podman are supported.
- Update project dependencies.

- Add `GRPCCredentialsTLS` class for improved TLS support.
- Add support for structured annotations in P4Schema.
- Add support for caching and reusing P4Defs as part of P4Schema.
- Add a py.typed file and improve type annotations.
- Add a `devcontainer.json` file for Github Codespace.
- Fix P4TableAction to allow an action that expects some arguments to be encoded with 0 arguments. Used for wildcard reads. (193)
- The Demonet sub-module now automatically tries docker if podman is not available.
- Replace flake8 with ruff, fix lint issues, and improve testing.