Clarify documentation for `ElectricalComponentStateCode`

[llucax]

The current documentation for ElectricalComponentStateCode does not make it clear which states can or should appear together, or how they relate to each other logically.

Developers have difficulty understanding what combinations are valid or expected, and the lack of clarity leads to confusion and potential misuse of the API.

Examples:

• Many states are mutually exclusive (e.g., STANDBY, READY, CHARGING, DISCHARGING, ERROR), and only one should be present at a time—this should be documented explicitly.

• Specialized states such as EV_CHARGING_CABLE_LOCKED_AT_EV, PLUGGED, or UNPLUGGED should have rules about exclusive or combinable usage. For example, LOCKED_EV should not appear with PLUGGED_EV or UNPLUGGED, and at most one "_STATION" and one "_EV" state should be present simultaneously.

• For each component type, define what states like READY or STANDBY mean in practice, and how they should be interpreted.

• Consider adding state diagrams or tables to illustrate valid state transitions and combinations, especially for complex categories like EV chargers.

• Clarify which state(s) should always be present, and what the expected default is if a component is functional.