firmware & wireless refactor + extrepo Migration

- Created standalone modules/bluetooth.sh  for `_install_bluetooth_stack()` with desktop-aware frontend selection (bluedevil/KDE, blueman/XFCE/other). Extracted from `firmware.sh`, reducing it from 438 to 369 lines.

- Added `detect_desktop_environment()` and `detect_audio_server()` functions in `utils.sh` with new globals `DESKTOP_ENV=""` and `AUDIO_SERVER=""`.

- New `found_active_wifi` flag detects Qualcomm Atheros AR9485 PCI chips without loaded firmware, displaying `(no driver — install firmware)` instead of silently disappearing. Auto-installs `firmware-atheros + firmware-linux-nonfree` after Firmware & Wireless Setup.

- New `is_nvidia_blackwell()` detects GPUs in ranges `0x2900–0x29BF` and `0x2B80–0x31FF`. Added `_enable_cuda_repo()` helper for extrepo-based CUDA installation with APT pinning. DKMS verification blocks added to all `_install_nvidia_*` functions.

- Standardized repository enablement across 7 modules using `_enable_*_repo()` helpers:
  - `internet.sh`: Firefox/Floorp/LibreWolf, Pale Moon, Tailscale, Mullvad VPN/Browser, ProtonVPN
  - `jellyfin.sh`, `programming.sh` (VSCodium), `java.sh` (Temurin)
  - New `extras/office/office.sh`: OnlyOffice + LibreOffice with language detection

- The main script was reduced from 233 to 137 lines. Created new `modules/sysinfo.sh` (97 lines) for `_show_sysinfo()`. Source chain: `utils.sh → sysinfo.sh → sudo_config.sh → repos → firmware.sh → bluetooth.sh → gpu.sh → kernel.sh → gaming.sh → extras.sh → zram.sh → java.sh`.

- Renamed menu to `"Firmware, Wireless & Bluetooth"`. Translated NTP dialog (English), basic programs install message, and NVIDIA 32-bit legacy messages.

modules/extras.sh

@@ -39,9 +39,10 @@ install_extras() {
             "7" "Servers & Dev Tools" \
             "8" "Security & Networking" \
             "9" "Software Centers" \
-            "10" "System Tools" \
-            "11" "Fetch / System Info" \
-            "12" "Back to main menu" \
+            "10" "Office & Productivity" \
+            "11" "System Tools" \
+            "12" "Fetch / System Info" \
+            "13" "Back to main menu" \
             3>&1 1>&2 2>&3)
 
         [ -z "$cat_choice" ] && return
@@ -58,9 +59,10 @@ install_extras() {
             7)  _cat_dev ;;
             8)  _cat_security ;;
             9)  _cat_software_centers ;;
-            10) _cat_general ;;
-            11) _cat_fetch ;;
-            12) return ;;
+            10) _cat_office ;;
+            11) _cat_general ;;
+            12) _cat_fetch ;;
+            13) return ;;
         esac
         clear
     done