fix(scripts): use mktemp for state.json writes, not a fixed /tmp path

Ten state-mutating sites across seven scripts wrote through a predictable,
world-writable temp path (`/tmp/state.json`, `/tmp/system-state.json`)
before the atomic `sudo mv`. Because the `>` redirect runs as the invoking
user (sudo doesn't cover redirects), the shared fixed path is a symlink/
TOCTOU target and collides if two of these run concurrently. Switch each
to a per-invocation `mktemp`; the atomic rename into place is unchanged.
nomarchy-theme-set already used a temp var for its home-state write — this
makes its system-state write consistent and cleans the temp up on failure.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

core/system/scripts/nomarchy-setup-dns

@@ -14,7 +14,7 @@ fi
 
 case "$dns" in
 Cloudflare|Google|DHCP)
-  sudo jq --arg dns "$dns" '.dns = $dns' "$STATE_FILE" > /tmp/state.json && sudo mv /tmp/state.json "$STATE_FILE"
+  tmp=$(mktemp); sudo jq --arg dns "$dns" '.dns = $dns' "$STATE_FILE" > "$tmp" && sudo mv "$tmp" "$STATE_FILE"
   ;;
 
 Custom)
@@ -28,7 +28,7 @@ Custom)
 
   # Convert to JSON array safely
   dns_array=$(echo "$dns_servers" | jq -R 'split(" ")')
-  sudo jq --arg dns "Custom" --argjson servers "$dns_array" '.dns = $dns | .customDns = $servers' "$STATE_FILE" > /tmp/state.json && sudo mv /tmp/state.json "$STATE_FILE"
+  tmp=$(mktemp); sudo jq --arg dns "Custom" --argjson servers "$dns_array" '.dns = $dns | .customDns = $servers' "$STATE_FILE" > "$tmp" && sudo mv "$tmp" "$STATE_FILE"
   ;;
 esac
 

core/system/scripts/nomarchy-setup-fido2

@@ -6,13 +6,13 @@ set -e
 STATE_FILE="/etc/nixos/state.json"
 
 if [[ "--remove" == $1 ]]; then
-    sudo jq '.features.fido2 = false' "$STATE_FILE" > /tmp/state.json && sudo mv /tmp/state.json "$STATE_FILE"
+    tmp=$(mktemp); sudo jq '.features.fido2 = false' "$STATE_FILE" > "$tmp" && sudo mv "$tmp" "$STATE_FILE"
     echo "FIDO2 support disabled. Applying changes..."
     sudo nomarchy-sys-update
     exit 0
 fi
 
-sudo jq '.features.fido2 = true' "$STATE_FILE" > /tmp/state.json && sudo mv /tmp/state.json "$STATE_FILE"
+tmp=$(mktemp); sudo jq '.features.fido2 = true' "$STATE_FILE" > "$tmp" && sudo mv "$tmp" "$STATE_FILE"
 echo "FIDO2 support enabled. Applying changes..."
 sudo nomarchy-sys-update
 

core/system/scripts/nomarchy-setup-fingerprint

@@ -6,13 +6,13 @@ set -e
 STATE_FILE="/etc/nixos/state.json"
 
 if [[ "--remove" == $1 ]]; then
-    sudo jq '.features.fingerprint = false' "$STATE_FILE" > /tmp/state.json && sudo mv /tmp/state.json "$STATE_FILE"
+    tmp=$(mktemp); sudo jq '.features.fingerprint = false' "$STATE_FILE" > "$tmp" && sudo mv "$tmp" "$STATE_FILE"
     echo "Fingerprint support disabled. Applying changes..."
     sudo nomarchy-sys-update
     exit 0
 fi
 
-sudo jq '.features.fingerprint = true' "$STATE_FILE" > /tmp/state.json && sudo mv /tmp/state.json "$STATE_FILE"
+tmp=$(mktemp); sudo jq '.features.fingerprint = true' "$STATE_FILE" > "$tmp" && sudo mv "$tmp" "$STATE_FILE"
 echo "Fingerprint support enabled. Applying changes..."
 sudo nomarchy-sys-update
 

core/system/scripts/nomarchy-toggle-hybrid-gpu

@@ -9,7 +9,7 @@ STATE_FILE="/etc/nixos/state.json"
 # Check if supergfxd is enabled in config
 if [[ $(sudo jq -r '.features.hybridGPU // false' "$STATE_FILE") != "true" ]]; then
     if gum confirm "Hybrid GPU support is not enabled. Enable it now? (Requires sys-update)"; then
-        sudo jq '.features.hybridGPU = true' "$STATE_FILE" > /tmp/state.json && sudo mv /tmp/state.json "$STATE_FILE"
+        tmp=$(mktemp); sudo jq '.features.hybridGPU = true' "$STATE_FILE" > "$tmp" && sudo mv "$tmp" "$STATE_FILE"
         echo "Hybrid GPU support enabled in configuration. Applying changes..."
         sudo nomarchy-sys-update
         echo "Please run this command again after the update."

core/system/scripts/nomarchy-tz-select

@@ -7,7 +7,7 @@ STATE_FILE="/etc/nixos/state.json"
 
 timezone=$(timedatectl list-timezones | gum filter --height 20 --header "Set timezone") || exit 1
 
-sudo jq --arg tz "$timezone" '.timezone = $tz' "$STATE_FILE" > /tmp/state.json && sudo mv /tmp/state.json "$STATE_FILE"
+tmp=$(mktemp); sudo jq --arg tz "$timezone" '.timezone = $tz' "$STATE_FILE" > "$tmp" && sudo mv "$tmp" "$STATE_FILE"
 
 echo "Timezone is now set to $timezone. Applying changes..."
 sudo nomarchy-sys-update

core/system/scripts/nomarchy-wifi-powersave

@@ -12,7 +12,7 @@ off) value="false" ;;
 *) echo "Usage: nomarchy-wifi-powersave <on|off>"; exit 1 ;;
 esac
 
-sudo jq --argjson val "$value" '.wifi.powersave = $val' "$STATE_FILE" > /tmp/state.json && sudo mv /tmp/state.json "$STATE_FILE"
+tmp=$(mktemp); sudo jq --argjson val "$value" '.wifi.powersave = $val' "$STATE_FILE" > "$tmp" && sudo mv "$tmp" "$STATE_FILE"
 
 echo "Wifi powersave set to $1. Applying changes..."
 sudo nomarchy-sys-update