FFmpeg's protocol lookup is case-sensitive, so a stored "Https://" base
URL reaches mpv verbatim through the direct-play string concat and fails
with "Protocol not found" (API calls survive because Dart's Uri
lowercases the scheme). Canonicalize at Jellyfin URL intake and in the
connection constructor so persisted configs self-heal on load, and
register mpv-escaped (https\://) redaction variants so option-value
logs stop leaking the server host.
close#1465
Delete unused registry members (ProfileConnectionRegistry.insertIfAbsent /
removeAllForProfile, ProfileRegistry.reorder, ProfilesView.countFor,
ConnectionRegistry.getDefault) and their orphan tests, refreshing the stale
docs that named removeAllForProfile as the profile-delete cleanup path.
Repair the "one default per profile" join-row invariant: the connectionId FK
cascade (foreign_keys=ON) silently drops a profile's default row while its
other rows survive, leaving it defaultless. Add promoteMissingDefaults, share
a deterministic re-promotion helper with remove(), and re-promote in
removeAllForConnection.
edde746