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/alembic/versions/20260115_1800_005_lesson_reflections.py

@@ -0,0 +1,40 @@
+"""Add Lesson Reflections Table (Phase 5: Analytics)
+
+Erstellt die lesson_reflections Tabelle fuer
+Post-Lesson Reflexionen.
+
+Revision ID: 005
+Revises: 004
+Create Date: 2026-01-15 18:00:00
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+
+# revision identifiers, used by Alembic.
+revision: str = '005'
+down_revision: Union[str, None] = '004'
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    op.create_table(
+        'lesson_reflections',
+        sa.Column('id', sa.String(36), primary_key=True),
+        sa.Column('session_id', sa.String(36), sa.ForeignKey('lesson_sessions.id'), nullable=False, unique=True, index=True),
+        sa.Column('teacher_id', sa.String(100), nullable=False, index=True),
+        sa.Column('notes', sa.Text(), default=''),
+        sa.Column('overall_rating', sa.Integer(), nullable=True),
+        sa.Column('what_worked', sa.JSON(), default=list),
+        sa.Column('improvements', sa.JSON(), default=list),
+        sa.Column('notes_for_next_lesson', sa.Text(), default=''),
+        sa.Column('created_at', sa.DateTime(), server_default=sa.func.now()),
+        sa.Column('updated_at', sa.DateTime(), server_default=sa.func.now(), onupdate=sa.func.now()),
+    )
+
+
+def downgrade() -> None:
+    op.drop_table('lesson_reflections')