_onDispositivoCambiado() bootstrapped a device-level preset entry for
every never-seen device id, including the built-in speaker. That
persistent level-3 entry masked later global-preset edits (level 3
beats level 4 on every resolution), so disconnecting a BT device or
cold-starting without one could leave the EQ stuck on an outdated
copy instead of the current global preset.
The base speaker is now excluded from the first-seen bootstrap:
disconnect and cold start always resolve through the live hierarchy.
BT/wired/USB devices keep their bootstrap behavior unchanged.
