Fallback echo/log audit pass — fallback.sh, fallback_test.sh + Manual

Remove setup banners from fallback.sh and fallback_test.sh. Add Host Detection
to fallback.sh OPERATIONAL SAFEGUARDS; add Lock Acquisition + Host Detection to
fallback_test.sh. Add output tiers section to Manual-Fallback.md documenting
daemon vs one-shot output behaviour.

Fallback/Manual-Fallback.md

@@ -568,6 +568,24 @@ If it has happened:
 
 ---
 
+## ━━━ OUTPUT TIERS ━━━
+
+Both scripts have two output levels controlled by `--log`.
+
+**fallback.sh** — daemon, runs continuously. Without `--log`, only state transitions,
+warnings, errors, and the startup banner are visible. Per-cycle detail (ping results,
+state evaluation) is suppressed — the daemon runs every 15–30 seconds and clean cycles
+produce no output by design. State transitions are always visible because they are the
+events that matter. Use `--log` when debugging why the state machine is or is not
+acting.
+
+**fallback_test.sh** — one-shot test harness. Without `--log`, phase headers, pass/fail
+results, and the final test report are always visible. Per-container checks within each
+phase are suppressed. With `--log`, every check in every phase is shown. Warnings and
+errors are always visible regardless of `--log`.
+
+---
+
 ## ━━━ FLAG REFERENCE ━━━
 
 ### fallback.sh

Fallback/fallback.sh

@@ -111,6 +111,10 @@
 #   acquire_lock() prevents two instances running simultaneously. Both would
 #   modify containers and DDNS independently — conflict is certain.
 #
+# Host Detection
+#   detect_hosts() resolves MY_ID / REMOTE_ID from master.conf at startup.
+#   Exits if the host cannot be identified — prevents running on an unknown machine.
+#
 # Silent by Default
 #   State transitions: warn() — always visible. Healthy routine cycles: log()
 #   — suppressed unless --log. Produces no output on clean cycles.
@@ -246,8 +250,6 @@ fi
 # ==============================================================================================
 # ━━━ Setup ━━━
 # ==============================================================================================
-echo ""
-echo "━━━ $ICON_GEAR Setup ━━━"
 
 if [[ "$EUID" -ne 0 ]]; then
     error "Must be run as root"

Fallback/fallback_test.sh

@@ -60,6 +60,14 @@
 # Remote Docker Daemon Check
 #   Pre-flight confirms remote Docker daemon is responsive before Phase 2.
 #
+# Lock Acquisition
+#   acquire_lock() prevents concurrent test runs. Running two tests simultaneously
+#   would produce conflicting iptables rules and unreliable results.
+#
+# Host Detection
+#   detect_hosts() resolves MY_ID / REMOTE_ID from master.conf at startup.
+#   Exits if the host cannot be identified — prevents testing on an unknown machine.
+#
 # ==============================================================================================
 # CONFIGURATION
 # ==============================================================================================
@@ -134,8 +142,6 @@ trap cleanup EXIT
 # ==============================================================================================
 # ━━━ Setup ━━━
 # ==============================================================================================
-echo ""
-echo "━━━ $ICON_GEAR Setup ━━━"
 
 if [[ "$EUID" -ne 0 ]]; then
     error "Must be run as root"