fix: Restore all files lost during destructive rebase

A previous `git pull --rebase origin main` dropped 177 local commits,
losing 3400+ files across admin-v2, backend, studio-v2, website,
klausur-service, and many other services. The partial restore attempt
(660295e2) only recovered some files.

This commit restores all missing files from pre-rebase ref 98933f5e
while preserving post-rebase additions (night-scheduler, night-mode UI,
NightModeWidget dashboard integration).

Restored features include:
- AI Module Sidebar (FAB), OCR Labeling, OCR Compare
- GPU Dashboard, RAG Pipeline, Magic Help
- Klausur-Korrektur (8 files), Abitur-Archiv (5+ files)
- Companion, Zeugnisse-Crawler, Screen Flow
- Full backend, studio-v2, website, klausur-service
- All compliance SDKs, agent-core, voice-service
- CI/CD configs, documentation, scripts

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend/frontend/static/css/modules/components/communication.css

@@ -0,0 +1,155 @@
+/* ==========================================
+   Communication Panel Styles (Matrix + Jitsi)
+   Chat, Room List, Messages
+   ========================================== */
+
+/* Room List Styles */
+.room-item {
+  display: flex;
+  align-items: center;
+  gap: 10px;
+  padding: 10px 12px;
+  border-radius: 8px;
+  cursor: pointer;
+  transition: background 0.2s;
+}
+
+.room-item:hover {
+  background: var(--bp-surface-elevated);
+}
+
+.room-item.active {
+  background: var(--bp-primary-soft);
+  border-left: 3px solid var(--bp-primary);
+}
+
+.room-icon {
+  font-size: 20px;
+  width: 36px;
+  height: 36px;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  background: var(--bp-surface-elevated);
+  border-radius: 8px;
+}
+
+.room-info {
+  flex: 1;
+  min-width: 0;
+}
+
+.room-name {
+  font-weight: 500;
+  font-size: 13px;
+  color: var(--bp-text);
+  white-space: nowrap;
+  overflow: hidden;
+  text-overflow: ellipsis;
+}
+
+.room-preview {
+  font-size: 11px;
+  color: var(--bp-text-muted);
+  white-space: nowrap;
+  overflow: hidden;
+  text-overflow: ellipsis;
+}
+
+.room-badge {
+  background: var(--bp-primary);
+  color: white;
+  font-size: 10px;
+  font-weight: 600;
+  padding: 2px 6px;
+  border-radius: 10px;
+  min-width: 18px;
+  text-align: center;
+}
+
+/* Chat Message Styles */
+.chat-system-msg {
+  text-align: center;
+  padding: 8px 16px;
+  background: var(--bp-surface-elevated);
+  border-radius: 8px;
+  font-size: 12px;
+  color: var(--bp-text-muted);
+}
+
+.chat-msg {
+  padding: 12px 16px;
+  border-radius: 12px;
+  max-width: 85%;
+}
+
+.chat-msg-self {
+  background: var(--bp-primary-soft);
+  border: 1px solid var(--bp-border-subtle);
+  margin-left: auto;
+}
+
+.chat-msg-other {
+  background: var(--bp-surface-elevated);
+  border: 1px solid var(--bp-border);
+}
+
+.chat-msg-notification {
+  background: rgba(239, 68, 68, 0.1);
+  border: 1px solid rgba(239, 68, 68, 0.3);
+}
+
+.chat-msg-header {
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  margin-bottom: 6px;
+}
+
+.chat-msg-sender {
+  font-weight: 600;
+  font-size: 12px;
+  color: var(--bp-primary);
+}
+
+.chat-msg-time {
+  font-size: 10px;
+  color: var(--bp-text-muted);
+}
+
+.chat-msg-content {
+  font-size: 13px;
+  line-height: 1.5;
+  color: var(--bp-text);
+}
+
+.chat-msg-actions {
+  display: flex;
+  gap: 6px;
+  margin-top: 10px;
+  padding-top: 10px;
+  border-top: 1px solid var(--bp-border);
+}
+
+/* Button danger variant (global) */
+.btn-danger {
+  background: #ef4444 !important;
+  color: white !important;
+}
+
+.btn-danger:hover {
+  background: #dc2626 !important;
+}
+
+/* Light Mode Overrides */
+[data-theme="light"] .room-item.active {
+  background: var(--bp-primary-soft);
+}
+
+[data-theme="light"] .chat-msg-self {
+  background: var(--bp-primary-soft);
+}
+
+[data-theme="light"] .chat-msg-other {
+  background: var(--bp-bg);
+}