Type Alias SHLFlag

SHLFlag: "L" | "P" | "LP" | "U" | "LU"

SHL flags supported by this implementation.

Flags modify the behavior of SMART Health Links:

'L': Long-term - Recipients may poll the manifest URL for updates over time
'P': Passcode-protected - A passcode is required to access the manifest
'U': Direct file - Resolves to a single encrypted file accessible via GET, bypassing the manifest
'LP': Both long-term and passcode-protected
'LU': Both long-term and direct file

Flags are concatenated in the SHL payload (e.g., 'LP' means both L and P flags are set).