ProPresenter guard at every location: install.sh starts it where ProPresenter is, it finds ProPresenter's port, leaves a song already up alone; restart off by default

WS and SC updated to the current build (code only, their settings kept). NA's Resi cues polling slowed to 10 s / 20 s (Companion setting).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

README.md

@@ -366,6 +366,18 @@ SC's Lighting PC (SC Lighting PC, 10.5.1.168) keeps several copies of `Tiverton
 and starts Vista; a running Vista is left alone. `-WhatIf` shows the pick without changing anything. Running the PC join
 line again resets the task to plain `Vista.exe`: point it back at the script afterwards.
 
+## ProPresenter guard (every location with ProPresenter on the Companion Mac)
+
+`prop_guard.py` (LaunchAgent `org.waterschurch.prop-guard`, log `~/Library/Logs/prop-guard.log`) is started by
+`install.sh` on any Mac with `/Applications/ProPresenter*.app`: today SC and WS, and AB with its next package. When a
+song (a presentation with a timeline) comes up and its first slide's macro left the **Stage Display** screen (else the
+first stage screen) on a layout without "Worship" in its name, it is set to **Worship** within 12 s; later picks are left
+alone, and so is a song that was already up when the guard started. ProPresenter's network port differs per Mac
+(WS 49285, SC 50098) and moves now and then: when the set one does not answer, the guard finds it. Per-location
+settings go in `prop-guard.json.cfg` beside it (never overwritten). Restarting a stopped timeline is off unless that
+file says `{"resume": true}`. At SC, `LTC Listen.app` hears the tracks' timecode on SoundGrid, and the PROP key shows
+**TIMECODE LOST** (`http://127.0.0.1:8095/timecode`) when it stops in the middle of a song.
+
 ## A location on its own (Apollo Beach)
 
 Apollo Beach runs its panel itself: not on NA's deck, not in NA's backups, no NA key on its Macs.