Assigning a spool to an AMS tray pushed ams_filament_setting +
extrusion_cali_sel and reported success immediately, whether or not the
tray accepted it. A silently-dropped assignment never surfaced, and since
a print only deducts from the spool on the exact tray it pulls from, it
also recorded no filament usage - which made the whole thing feel random.
Read the AMS telemetry back after every assign (inventory assign_spool and
the Configure Slot modal) and toast the outcome: loaded when the tray
echoes the pushed tray_info_idx, a warning when the filament loaded but the
K-profile (cali_idx) did not, or not-confirmed after ~30s. Verification
uses the periodic per-tray push (the command ack hardcodes sequence_id 0
and can't be correlated); an on-demand pushall is nudged so it lands
quickly. Covers regular AMS, AMS-HT and external slots; stays silent rather
than inventing a failure if the printer goes quiet. The read-back check
runs on every AMS push because the change-hash excludes tray_info_idx.
