load_config: source partner confs from /tmp cache

conf_sync.sh has always populated /tmp/.vv/config/cached/.confs/ with
partner host*.conf files pulled via SCP, but load_config.sh never read
from it — leaving HOST2_* vars undefined on HOST1 and vice versa.

After the disk host*.conf loop, source any cached conf whose basename
wasn't already loaded from disk. Disk copy always wins (authoritative);
cache supplies partner vars that sparse checkout intentionally withholds.
Cache is tmpfs, cleared on reboot, repopulated by conf_sync.sh on array
start.

load_config.sh

@@ -80,12 +80,14 @@
 # Missing files are silently skipped — sparse checkout intentionally withholds some.
 # At least one host conf must be present or the ecosystem has no identity to work with.
     _host_confs_loaded=0
+    declare -A _disk_conf_basenames=()
 
     # Use a sorted array glob — avoids word-splitting on paths with spaces
     while IFS= read -r _conf; do
         [[ -f "$_conf" ]] || continue
         source "$_conf"
         (( _host_confs_loaded++ ))
+        _disk_conf_basenames["$(basename "$_conf")"]=1
         [[ "${ENABLE_LOGGING:-false}" == "true" ]] && \
             echo "[LOG] Loaded host config: $(basename "$_conf")" >&2
     done < <(printf '%s\n' "$LOAD_CONFIG_DIR/Configurations"/host*.conf 2>/dev/null | sort)
@@ -96,6 +98,26 @@
         exit 1
     fi
 
+# ━━━ Source partner confs from /tmp cache ━━━
+# conf_sync.sh pulls partner host*.conf files into /tmp/.vv/config/cached/.confs/
+# on array start and after any conf save. Sourcing them here makes partner vars
+# (HOST2_*, HOST3_*, …) available without committing credentials to the git repo
+# or violating sparse checkout — partner confs live in RAM only, cleared on reboot.
+# Confs already loaded from disk are skipped — disk copy is authoritative.
+    _VV_CONF_CACHE="/tmp/.vv/config/cached/.confs"
+    if [[ -d "$_VV_CONF_CACHE" ]]; then
+        while IFS= read -r _conf; do
+            [[ -f "$_conf" ]] || continue
+            _conf_base="$(basename "$_conf")"
+            # Skip if already sourced from disk
+            [[ -n "${_disk_conf_basenames[$_conf_base]:-}" ]] && continue
+            source "$_conf"
+            [[ "${ENABLE_LOGGING:-false}" == "true" ]] && \
+                echo "[LOG] Loaded cached partner config: $_conf_base" >&2
+        done < <(printf '%s\n' "$_VV_CONF_CACHE"/host*.conf 2>/dev/null | sort)
+    fi
+    unset _VV_CONF_CACHE _conf_base _disk_conf_basenames
+
 # ━━━ Source shared functions ━━━
 # common.sh sourced last — it calls detect_hosts() which needs HOST* vars to be set.
     if [[ ! -f "$LOAD_CONFIG_DIR/common.sh" ]]; then