Collections shared with the account are not encrypted with the master
key: the sharer only knows the recipient's public key, so the server
delivers encryptedKey as crypto_box_seal to that key and omits
keyDecryptionNonce entirely. decryptCollection assumed the owned-only
wire format and crashed on fromBase64(undefined) for any account with
an incoming shared album, taking down listCollections and every
command built on it (backup, backup-metadata, ...).
The previous "shared" fixture was unfaithful (secretbox + nonce with a
foreign ownerID, a shape the server never sends), which is why the
suite stayed green. These tests model the real wire format and change
decryptCollection to take the full key material {masterKey, publicKey,
secretKey} so it can unseal shared collection keys.
German for 'quack', matching the Ente (German for 'duck') naming. All
references updated: package name, CLI binary, X-Client-Package header,
test descriptions, temp dir prefixes, README, Makefile docker tag.
File metadata is encrypted as a single-chunk secretstream blob (the
'decryptionHeader' is the secretstream init header, not a secretbox
nonce). Collection keys and names correctly use secretbox.
Adds decryptBlob(ciphertext, header, key) to the crypto module as a
convenience wrapper for single-chunk secretstream decryption (init +
pull + verify TAG_FINAL).
Live-tested: collection names and file metadata (titles, types, dates)
decrypt correctly from the real Ente API.
10 tests covering decryptCollection (key + name decryption from raw
server JSON, type mapping, isShared, missing name, wrong key) and
decryptFile (key + metadata decryption, fileType number-to-string
mapping, file/thumbnail header passthrough, wrong key).
Adds src/model/types.ts with both raw (server) and decrypted (library)
type definitions. src/model/decrypt.ts has throwing stubs.
