Merge all notifications

Notification for kernel update is included in the same notification as
everything else, no more a separate one

update-notify

@@ -93,29 +93,37 @@ updates=$((arch_updates + aur_updates))
 # ---------------------------------------------------------------------------
 # Kernel check: the stock kernel updated, but your custom build didn't
 # ---------------------------------------------------------------------------
+kernel_lines=()
 for stock_pkg in "${!KERNELS[@]}"; do
     custom_pkg=${KERNELS[$stock_pkg]}
 
     # Skip kernels where either package isn't installed
     if ! stock_ver=$(latest_version "$stock_pkg") || ! custom_ver=$(latest_version "$custom_pkg"); then
-        clear_state "kernel-$stock_pkg"
         continue
     fi
 
-    # Notify while the stock kernel is newer than the newest custom build
+    # Flag the kernel while the stock one is newer than the newest custom build
     # (installed, or already built into your repo but not yet installed)
     if (( $(vercmp "$stock_ver" "$custom_ver") > 0 )); then
-        notify_once "kernel-$stock_pkg" "Kernel update available: $stock_pkg" \
-            "Rebuild $custom_pkg ($stock_pkg $stock_ver)"
-    else
-        clear_state "kernel-$stock_pkg"
+        kernel_lines+=("Rebuild $custom_pkg ($stock_pkg $stock_ver)")
     fi
 done
 
 # ---------------------------------------------------------------------------
-# General updates threshold
+# Build a single notification
+#   - kernel rebuild lines are always included
+#   - update counts and reminders only when the threshold is reached
 # ---------------------------------------------------------------------------
-if (( updates >= threshold )); then
+over_threshold=0
+(( updates >= threshold )) && over_threshold=1
+
+parts=()
+if (( over_threshold )); then
+    parts+=("Arch: $arch_updates, AUR: $aur_updates")
+fi
+parts+=("${kernel_lines[@]}")
+
+if (( over_threshold )); then
     reminders=()
 
     # Always remind about git packages if git-monitor is installed
@@ -133,13 +141,17 @@ if (( updates >= threshold )); then
         fi
     fi
 
-    body="Arch: $arch_updates, AUR: $aur_updates"
     if (( ${#reminders[@]} )); then
         printf -v list '%s, ' "${reminders[@]}"
-        body+=$'\n'"Also check: ${list%, }"
+        parts+=("Also check: ${list%, }")
     fi
+fi
 
-    notify_once "updates" "Updates available" "$body"
+if (( ${#parts[@]} )); then
+    title="Updates available"
+    (( over_threshold )) || title="Kernel update available"
+    printf -v body '%s\n' "${parts[@]}"
+    notify_once "updates" "$title" "${body%$'\n'}"
 else
     clear_state "updates"
 fi