Refactor enums, freeathome, pairing

[kingsleyadam]

This PR refactors the ENUM's to remove the id naming convention.

• FunctionID --> Function
• ParingID --> Pairing

ID becomes a bit confusing as it's not an ID, it's an ENUM and the value is an ID.

I've also changed the FreeAtHome object to expose self._api as a public attribute self.api in case we would need to use the api externally (e.g. Home Assistant using the FreeAtHome class to fetch a value from the API). I don't have a use case yet but it's possible.

[github-actions]

Package	Line Rate	Complexity	Health
.opt.hostedtoolcache.Python.3.12.7.x64.lib.python3.12.site-packages.abbfreeathome	100%	0	✔
.opt.hostedtoolcache.Python.3.12.7.x64.lib.python3.12.site-packages.abbfreeathome.bin	100%	0	✔
.opt.hostedtoolcache.Python.3.12.7.x64.lib.python3.12.site-packages.abbfreeathome.devices	100%	0	✔
Summary	100% (1065 / 1065)	0	✔

[github-actions]

	Tests	Passed ✅	Skipped ⏭️	Failed ❌
JUnit Test Report	61 ran	61 passed	0 skipped	0 failed

	Test	Result
-	No test annotations available	-