Makes the integration fully self-contained for HACS distribution.
Users installing via HACS get everything in one directory; no external
samsung_appliance package needed.
All component imports updated to relative (.ocf.*); all test imports
updated to custom_components.localthings.ocf.*. ocf_root_ca.pem moves
with the package and resolves correctly via Path(__file__).parent.
Registry changes from dict[str,Capability] to dict[str,list[Capability]].
discover() gains pattern_caps parameter (fallback for unmatched hrefs)
and gates each candidate on rt_filter and match_fn before binding.
Duplicate hrefs in registry allowed only if all caps set a discriminator.
OCF rt is a schema category shared by many unrelated resources.
The stable unique resource address is the href. Update Capability,
discovery, common capabilities, tests, and plan accordingly.