Merge upstream main: add DMR, WebSDR, HF SSTV, alerts, recordings, waterfall

Merges upstream changes into fork while preserving weather satellite
(NOAA APT/Meteor LRPT via SatDump), rtlamr, multi-arch build, and
decoder console features from our branch.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

docker-compose.yml

@@ -112,7 +112,8 @@ services:
       - POSTGRES_USER=intercept
       - POSTGRES_PASSWORD=intercept
     volumes:
-      - ./pgdata:/var/lib/postgresql/data
+      # Default local path (override with PGDATA_PATH for external storage)
+      - ${PGDATA_PATH:-./pgdata}:/var/lib/postgresql/data
     restart: unless-stopped
     healthcheck:
       test: ["CMD-SHELL", "pg_isready -U intercept -d intercept_adsb"]