Support blob-encrypted ciphers and match upstream's key id checks

migrations/mysql/2026-10-08-120000_cipher_data_longtext/up.sql

@@ -0,0 +1,3 @@
+-- A blob-encrypted cipher keeps all of its content in `data`, up to 500,000 characters, so the
+-- 64 KiB of TEXT is too small. Like upstream, which uses LONGTEXT.
+ALTER TABLE ciphers MODIFY data LONGTEXT NOT NULL;