nixos/home: Separate router storage and uplinks

Give `river` a dedicated RDMA VF and two RSTP trunk attachments.
Keep client services on the router VIPs and carry Digiweb VLANs
over both switch paths.

Set VF trust, multicast reception, bridge MAC and ARP behavior for
local switching. Wait for Kea interface readiness and apply RSTP
costs through `mstpd` despite port-registration and rename races.

Load `palace`'s RAID module in the initrd. Record RouterOS and
RouterBOOT upgrades and validate port, carrier and switch outages.

Document the deployed architecture, interface handoffs and recovery
procedures. Add physical socket maps, NIC capacities and cable
connections alongside the logical topology and failover checks.

nixos/boxes/home/routing-common/mstpd.nix

@@ -6,6 +6,34 @@ let
     # Delete postInstall since it nukes the bridge-stp script we need
     postInstall = "";
   };
+  configureRSTP = pkgs.writeShellScript "configure-router-rstp" ''
+    set -eu
+    [ "$1" = lan ] || exit 0
+    event_port="''${2:-}"
+    ${mstpd}/bin/mstpctl addbridge lan
+    ${mstpd}/bin/mstpctl setforcevers lan rstp
+    for port in lan-dave lan-jim; do
+      if [ "$event_port" = "$port" ] || [ -e "/sys/class/net/lan/brif/$port" ]; then
+        case "$port" in
+          lan-dave) cost=10 ;;
+          lan-jim) cost=100 ;;
+        esac
+        # networkd can report configuration before mstpd has registered the port.
+        configured=false
+        for attempt in {1..50}; do
+          if ${mstpd}/bin/mstpctl setportpathcost lan "$port" "$cost"; then
+            configured=true
+            break
+          fi
+          ${pkgs.coreutils}/bin/sleep 0.2
+        done
+        if [ "$configured" = false ]; then
+          echo "Failed to configure RSTP cost for $port" >&2
+          exit 1
+        fi
+      fi
+    done
+  '';
 in
 {
   environment = {
@@ -17,6 +45,7 @@ in
       "bridge-stp.conf".text = ''
         MANAGE_MSTPD=n
         MSTP_BRIDGES=lan
+        config_cmd=${configureRSTP}
       '';
     };
   };
@@ -27,8 +56,9 @@ in
         onState = [ "configured" ];
         script = ''
           #!${pkgs.runtimeShell}
-          if [ "$IFACE" = "lan" ]; then
-            ${mstpd}/sbin/mstpctl setforcevers "$IFACE" rstp
+          # A queued event can retain the interface's name from before a rename.
+          if [ -d /sys/class/net/lan/bridge ]; then
+            ${configureRSTP} lan "$IFACE"
           fi
         '';
       };