Document today's restructures, and give data/ a README that ships with it

System_Essentials/README-System_Essentials.md

@@ -35,7 +35,7 @@ any container-connecting or continuous scripts start.
 **Partner Conf Lost Across Reboots When Partner is Down**
 Scripts like `fallback.sh` need the partner's conf vars (credentials, container
 names, tier delays) to operate. The partner conf lives in a RAM cache at
-`/tmp/.cache/vv/d/` — wiped every reboot. At array start, `conf_sync.sh` pulls
+`/tmp/varaverk/conf/` — wiped every reboot. At array start, `conf_sync.sh` pulls
 a fresh copy from the partner. But if the partner is offline at boot time, the
 pull fails and fallback has no partner vars to work with.
 
@@ -120,16 +120,16 @@ Plugin/unraid/Watchdogs/System/
 ```
 Array starts (array_started.sh, ARRAY_START_SCRIPTS):
     │
-    ├─ conf_sync.sh              ← SSH/SCP: pull partner confs into /tmp/.cache/vv/d/
-    │                              push own conf to partner's /tmp/.cache/vv/d/
+    ├─ conf_sync.sh              ← SSH/SCP: pull partner confs into /tmp/varaverk/conf/
+    │                              push own conf to partner's /tmp/varaverk/conf/
     ├─ conf_cache_restore.sh     ← if partner was down: load last-known-good conf from
-    │                              $PERSISTENT_CONF_CACHE into /tmp/.cache/vv/d/
+    │                              $PERSISTENT_CONF_CACHE into /tmp/varaverk/conf/
     ├─ docker_syslog_filter.sh   ← before any container starts (veth filter must be live)
     └─ inotify_tuning.sh         ← before docker_network_connect.sh and continuous scripts
 
 Array stops (array_stopping.sh, ARRAY_STOP_SCRIPTS):
     │
-    ├─ conf_cache_save.sh        ← FIRST: snapshot /tmp/.cache/vv/d/ → $PERSISTENT_CONF_CACHE
+    ├─ conf_cache_save.sh        ← FIRST: snapshot /tmp/varaverk/conf/ → $PERSISTENT_CONF_CACHE
     │                              while RAM cache is still fresh
     ├─ rsync_stop.sh --rsync-only ← kill active rsync, skip container recovery
     └─ ...other stop scripts...