Creates a single sample of the chosen sample type, optionally with meta-field values and an initial quantity. Use this for one-off creates from your client; for bulk imports prefer POST /samples/bulk.

Behaviour to know about:

• By default the call does not create any meta fields, even when the sample type marks them required. Set autoCreateMetaDefaults=true (query parameter) to populate meta fields whose sample-type definition has a default value or auto-numbering — fields without either are still skipped.
• quantitySettings is optional. Leave it out for samples whose type doesn't track quantity. If the sample type has quantityRequired set, omitting quantitySettings is rejected with 400.
• sampleMetas may be omitted (treated as empty), but values you supply must reference meta keys that exist on the sample type.

Returns the new sampleID.