Displays managers & zram menu

- LightDM Overhaul: Rewrote `install_lightdm()` logic to verify both lightdm and lightdm-gtk-gtk-greeter-settings. Now installs the trio in a single command if missing, skipping only when fully present. Added "Enable autologin" option modifying `/etc/lightdm/lightdm.conf` with robust `sed` patterns for `SUDO_USER`. Fixed missing `debconf-set-selections` to ensure LightDM is set as default during installation.
- GDM3 Implementation: Created a new sub-menu in `modules/desktop_display.sh` allowing independent installation of GDM3, User List toggle (hide/show), Autologin configuration via `/etc/gdm3/daemon.conf`, and conditional "Force Enable Wayland on NVIDIA" for Debian 12/13 using udev symlinks.
- SDDM Integration: Added SDDM as option 3 in the Display Manager menu. Implemented automatic session detection (Wayland > X11) to populate `/etc/sddm.conf.d/autologin.conf` without user input, defaulting to plasmawayland, lxqt-wayland, or generic fallbacks.
- greetd support: Added conditional support for Debian 12 and 13 only. Implemented sub-menu with base install, recommended `tuigreet` (with backports handling for Bookworm), and other manual setup options (`gtkgreet`, `nwg-hello`, `wlgreet`) exclusive to Trixie. 
- ZRAM UX Improvements: Updated descriptions in `modules/zram.sh` to explicitly mention I/O reduction and responsiveness benefits for low-RAM systems (e.g., 4GB). Cleaned up compression algorithm labels (`lz4`, `zstd`) to remove redundancy in menu values.
- General Code Quality: Standardized all user-facing messages to English across modules. Ensured independent package installation checks prevent script abortion if one DM fails, while maintaining strict error handling for system configurations.
- update docs and readme

docs/gpu.md

@@ -51,7 +51,7 @@ This "detect-then-deploy" model prevents users from installing unnecessary drive
 | **Gen7** (Ivy Bridge) | 22nm | HD Graphics 2500/4000 | `i915` | `crocus` | `ANV/HASVK` [(incomplete/broken)](https://www.reddit.com/r/vulkan/s/Hnf5zU8WZY) | First Gen at 22nm. `crocus` is the recommended OpenGL driver. Vulkan is exposed but completely non-conformant (0.0.0.0 ), lacks basic features (e.g., texture swizzle), and is [unusable for real-world tasks](https://www.phoronix.com/news/Intel-HasVK-Drop-Dead-Code).|
 | **Gen7** (Bay Trail) | 22nm | HD Graphics (Bay Trail) | `i915` | `crocus` | `ANV`[(incomplete)](https://lists.debian.org/debian-user/2023/07/msg00550.html) | `conformanceVersion = 0.0.0.0` Support is experimental up to Vulkan 1.2, lacks basic extensions, and may cause instability. The separate HASVK driver exists but is not used on this system. |
 | **Gen7.5** (Haswell) | 22nm | HD Graphics 4600, Iris Pro 5200 | `i915` | `crocus` | `hasvk` |  Vulkan support via community driver `hasvk` (Vulkan 1.3). |
-| **Gen8** (Broadwell) | 14nm | HD Graphics 5300, Iris Pro 6200, Iris 6100 | `i915` | `iris/crocus` | `hasvk` | First generation at 14nm, `iris` becomes the main OpenGL driver. |
+| **Gen8** (Broadwell) | 14nm | HD Graphics 5300, Iris Pro 6200, Iris 6100 | `i915` | `iris` | `hasvk` | First generation at 14nm, `iris` becomes the main OpenGL driver. |
 | **Gen9** (Skylake) | 14nm | HD Graphics 530, Iris 540/550 | `i915` | `iris` | `anv` | Mature architecture with strong Linux support. Major performance boost for iGPU. |
 | **Gen9.5** (Kaby Lake, Coffee Lake, Comet Lake) | 14nm+ / 14nm++ | UHD Graphics 620/630, UHD 610/630 | `i915` | `iris` | `anv` | Process node optimization for 14nm. "UHD" replaces "HD" in naming convention. |
 | **Gen11** (Ice Lake) | 10nm | UHD Graphics G1, Iris Plus G4/G7 | `i915` | `iris` | `anv` | First architecture at 10nm. Vulkan 1.3+ support. |