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>

agent-core/__init__.py

@@ -0,0 +1,24 @@
+"""
+Breakpilot Agent Core - Multi-Agent Infrastructure
+
+This module provides the shared infrastructure for Breakpilot's multi-agent architecture:
+- Session Management: Agent sessions with checkpoints and heartbeats
+- Shared Brain: Memory store, context management, and knowledge graph
+- Orchestration: Message bus, supervisor, and task routing
+"""
+
+from agent_core.sessions import AgentSession, SessionManager, SessionState
+from agent_core.brain import MemoryStore, ConversationContext
+from agent_core.orchestrator import MessageBus, AgentSupervisor, AgentMessage
+
+__version__ = "1.0.0"
+__all__ = [
+    "AgentSession",
+    "SessionManager",
+    "SessionState",
+    "MemoryStore",
+    "ConversationContext",
+    "MessageBus",
+    "AgentSupervisor",
+    "AgentMessage",
+]