fix: resolve all dialyzer type errors across project (46→0 project errors)
Type spec fixes:
- duct_usable_* return boolean→float (delegate to duct_usable_for_band)
- sanitize/1 spec includes :unicode error tuples
- match_delete/1 broadened from :ets.match_spec()
- telemetry_event local type replaces :telemetry.event/0
- wgrib2 parse_lon_val_segment corrected to tuple spec
- preloaded Ecto assoc types in get_mission/get_contact! specs
Unmatched returns:
- _ = prefix on Task.start, Oban.insert, Repo.query!, PubSub.subscribe,
:ets.new, and if-expression returns across 18 files
Pattern match fixes:
- markdown: restructure acc!=[] guard as direct pattern match
- path_compute/pskr/skewt_location_resolver: remove dead clauses
- calibrate.aprs_144: remove unreachable format_float catch-all
- unused.ex: suppress MapSet.union no_opaque
Also: remove unused unicode_util_compat from mix.lock
Graham McIntire
d67186176f