Added fediverse bridge draft

roles/web-app-bridgy-fed/templates/env.j2

@@ -0,0 +1,18 @@
+# Flask / Gunicorn basics
+FLASK_ENV="{{ ENVIRONMENT | default('production') }}"
+PORT="{{ container_port }}"
+BRIDGY_ADMIN_EMAIL="{{ BRIDGY_ADMIN_EMAIL }}"
+
+# Bridgy Fed upstream knobs (see README @ GitHub)
+APPVIEW_HOST="{{ APPVIEW_HOST }}"
+PLC_HOST="{{ PLC_HOST }}"
+BGS_HOST="{{ BGS_HOST }}"
+PDS_HOST="{{ PDS_HOST }}"
+
+# Datastore emulator (Datastore-mode Firestore). If sidecar enabled, point here.
+GOOGLE_CLOUD_PROJECT="{{ EMULATOR_PROJECT_ID }}"
+DATASTORE_EMULATOR_HOST="{{ EMULATOR_ENABLED | ternary(EMULATOR_HOST_INTERNAL, '') }}"
+# DATASTORE_DATASET not needed when GOOGLE_CLOUD_PROJECT is set
+
+# Optional:
+# GUNICORN_CMD_ARGS="--log-level info"