validateChannelName
Validates the name of a PostgreSQL channel to ensure it adheres to the naming rules.
A valid PostgreSQL channel name:
Must start with a letter or an underscore.
May be followed by letters, digits, or underscores.
Has a maximum length of 63 characters.
Parameters
channel
The name of the PostgreSQL channel to be validated.
Throws
If the channel name is invalid or does not conform to the rules.