The discovery retry timer turned adapter.discovering on every second
while the panel was open, and nothing ever turned it off. The BlueZ
discovery session behind it is held by quickshell's D-Bus connection,
so one visit to the panel left the radio in inquiry until the next
shell restart — continuously starving A2DP audio on the same controller
into stuttering, and 'bluetoothctl show' kept reporting
'Discovering: yes' long after the panel was gone.
The panel now tracks the StopDiscovery it owes BlueZ and settles it
once closed. A timer bound to the confirmed discovery state does the
stopping, rather than a write in the close handler: quickshell only
forwards a discovering write that differs from the last state BlueZ
reported, so a stop issued while a just-fired StartDiscovery is still
awaiting confirmation would be swallowed and leak the session. Binding
to adapter.discovering re-arms the stop whenever the confirmation
lands, a reopen inside the first interval keeps the scan running
uninterrupted, and attempts are bounded so a session another BlueZ
client holds up cannot draw StopDiscovery calls forever.
One widget instance exists per monitor and they all share the default
adapter — the same shared-backend shape the network panel's wifi
scanner fix (#6772) dealt with — so the debt follows the session: an
instance opening onto a running scan adopts it, a closing instance
hands it to a panel still open on another monitor (the popout handoff
closes one instance as it opens the next), and a destroyed instance
passes it to a surviving sibling.
Fixes#6789
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
