asterisk: 24.0.0-rc2 image built from source with static config

Adds stub configs and noloads so a clean boot logs no ERROR lines,
ships stock indications.conf, seeds default MOH from the entrypoint.
Spec 01 synced with the real files.

Task: M0-T5

asterisk/conf/features.conf

@@ -0,0 +1,11 @@
+[general]
+transferdigittimeout = 3
+xfersound = beep
+xferfailsound = beeperr
+pickupexten = *8
+featuredigittimeout = 1000
+
+[featuremap]
+blindxfer = ##
+atxfer = *2
+automixmon = *1       ; on-demand recording toggle (needs Dial option X)