v0.4.4

Fixed

• SingGuardClient keeps a longer writeup. to_result clipped explanation at 4000
  characters, which cut cascade/slow reasoning mid-sentence. The cap is now 16384, enough
  for a 2048-token slow writeup plus a cascade preface.
• Re-recording an asset no longer erases what another stage recorded on it. record_asset's
  upsert on sha256 replaced immich_id and metadata outright, so argus-lens recording a caption
  for an image argus-quarry had already recorded (licence, author, source) wiped that provenance,
  and a call without an immich_id cleared the stored one. metadata now merges key by key
  (jsonb ||: the new call's keys win, others are kept) and a NULL immich_id keeps the stored
  one. uri is still last-write-wins: it is the asset's latest location. A caller that needs to
  remove a metadata key can no longer do it through record_asset.