Remove swappy, obs-studio and meld

Update flake.lock to bump noctalia-shell and opencode inputs.
Tidy minor comments in desktop.nix and theming.nix.

flake.lock

@@ -143,11 +143,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1770150024,
-        "narHash": "sha256-sX7I5MJYDVJePQluHr+fL7iG38orZYYYyBCye/xLN1c=",
+        "lastModified": 1770151203,
+        "narHash": "sha256-2WgYoleZEK68KKnv4HBB+vVsf4tO1uTD5maBCWJvNIU=",
         "owner": "noctalia-dev",
         "repo": "noctalia-shell",
-        "rev": "505d6343e078f9a0288bbf16a78d5d7fd72aeeba",
+        "rev": "eb3c906a10a88b64af814f7c03b1584bd7ea52a8",
         "type": "github"
       },
       "original": {
@@ -163,11 +163,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1770148384,
-        "narHash": "sha256-Zv7FHwvaxSyPhXmsaOjxZdyWViVSKZTakT3RGbKNXcg=",
+        "lastModified": 1770151914,
+        "narHash": "sha256-eifY4uRtn5A1fJB+EJeU7ZAqFARV5vetbiL185zNLRY=",
         "owner": "anomalyco",
         "repo": "opencode",
-        "rev": "82dd4b69080afe623c89cd279a980a99e31a2c6a",
+        "rev": "17e62b050f744adcc9ca30f59ab9ed45ba3184f8",
         "type": "github"
       },
       "original": {

modules/apps.nix

@@ -61,10 +61,7 @@
     # ═══════════════════════════════════════════════════════════════
     # SCREENSHOTS & RECORDING
     # ═══════════════════════════════════════════════════════════════
-    swappy # Screenshot annotation tool
-
     # Screen recording
-    obs-studio # Full-featured streaming/recording suite
     gpu-screen-recorder # Lightweight GPU-accelerated recorder (AMD/NVIDIA/Intel)
 
     # ═══════════════════════════════════════════════════════════════
@@ -80,7 +77,6 @@
     gnome-clocks # World clocks, alarms, timers
     baobab # Disk usage analyzer
     localsend # AirDrop-like file sharing (cross-platform)
-    meld # Visual diff and merge tool
 
     # ═══════════════════════════════════════════════════════════════
     # SYSTEM TOOLS

modules/desktop.nix

@@ -25,7 +25,7 @@
   # GUI privilege escalation
   security.polkit.enable = true;
 
-  # Polkit authentication agent (runs on login)
+  # Polkit authentication agent
   systemd.user.services.polkit-gnome-agent = {
     description = "Polkit GNOME Authentication Agent";
     wantedBy = [ "graphical-session.target" ];

modules/theming.nix

@@ -68,8 +68,6 @@
     # Icon theme
     papirus-icon-theme # Modern, flat icons
 
-    # Cursor theme (Adwaita cursor is included in adwaita-icon-theme above)
-
     # Qt theming
     libsForQt5.qt5ct # Qt5 configuration tool
     kdePackages.qt6ct # Qt6 configuration tool