Module docid 

Document-identity minting: 128-bit ULID encoded as 26 Crockford base-32 chars. Deterministic under injected Clock + Rng for testability.

Functions

mint_ulid

Mint a fresh ULID document id: 48-bit millisecond timestamp (from clock) in the high bits, 80 bits of randomness (from rng) in the low bits.