feat(notify): add --silent flag, volume knob, and level sound files

The touchpad toggle's notification was too loud, and the eight notify sounds varied by ~13 dB in RMS loudness — bug and fail came out two to three times louder than info or security.

I added a --silent flag to notify (shows the popup, plays no sound) and a NOTIFY_VOLUME knob (paplay scale, default 65536) so the master level can drop without re-encoding. toggle-touchpad now passes --silent on both enable and disable. normalize-notify-sounds.sh measures each .ogg and shifts it to a uniform -31 dB mean. It writes through the file instead of mv-ing over it, so the stow symlinks survive when the script runs against the live sound dir. I re-encoded all eight sounds to the new level.

Tests: a new tests/notify suite (12 tests) covers --silent, the volume knob, flag composition, and the error paths.

1 files changed, 2 insertions, 2 deletions

diff --git a/dotfiles/hyprland/.local/bin/toggle-touchpad b/dotfiles/hyprland/.local/bin/toggle-touchpad
index cab605b..ed11674 100755
--- a/dotfiles/hyprland/.local/bin/toggle-touchpad
+++ b/dotfiles/hyprland/.local/bin/toggle-touchpad
@@ -14,11 +14,11 @@ state=$(cat "$STATE_FILE")
 if [ "$state" = "enabled" ]; then
     hyprctl keyword "device[$TOUCHPAD]:enabled" false >/dev/null
     echo "disabled" > "$STATE_FILE"
-    notify info "Touchpad" "Disabled"
+    notify info "Touchpad" "Disabled" --silent
 else
     hyprctl keyword "device[$TOUCHPAD]:enabled" true >/dev/null
     echo "enabled" > "$STATE_FILE"
-    notify info "Touchpad" "Enabled"
+    notify info "Touchpad" "Enabled" --silent
 fi
 
 # Refresh the waybar indicator immediately (custom/touchpad listens on signal 9).