Fix guild UI, also make Guild hideout stay up even when guild leader gets offline.

System:
RTX 5080 (16 GB VRAM)
Ryzen 7 9800X3D
Samsung 9100 NVMe SSD
Windows 11

Drivers / Rendering Tests:
NVIDIA:
Latest NVIDIA driver tested
Previous NVIDIA driver tested (clean installs)
AMD:
Tested AMD Adrenalin 25.9.1 after previously being on the newest AMD driver
Renderers tested: DX12 and Vulkan
Upscalers tested: DLSS, FSR, and no upscaling

Symptoms:
Guild UI consistently causes UI flicker and global color/gamma changes

Short but severe freeze-lags (frame stalls), not gradual FPS drops
Freeze-lags occur even when idle in hideout

Changing upscalers, renderers, or GPU drivers does not eliminate the issue (only minor behavior differences)

Performance metrics during freezes (PoE in-game overlay):
CPU frame time: ~2 ms
GPU frame time: ~3 ms
VRAM usage: ~5–7 GB (well below GPU limit)
System RAM usage: ~2–3 GB
Disk activity: 0–3 MB/s
Network latency: ~17 ms (stable)

Despite low CPU/GPU frame times, low VRAM usage, and minimal disk activity on a high-speed NVMe SSD, the frame-time graph shows sharp red spikes that result in visible freezes.

What this rules out:
Not VRAM exhaustion
Not disk or asset streaming (Samsung 9100 NVMe, disk idle during stalls)
Not shader compilation from disk
Not network-related
Not GPU driver specific (both NVIDIA drivers and AMD Adrenalin 25.9.1 tested)
Not hardware-related

Conclusion: This appears to be an engine-level regression introduced in 0.4, likely related to UI/state rebuilds and post-processing or color pipeline synchronization causing main-thread stalls.
The issue is reproducible while idle and is triggered more often by UI interaction (especially Guild UI). There is currently no client-side workaround that fully resolves it.

Posting for visibility and investigation.