feat: AI Kurzy module, project/service documents, services SQL import

- Add AI Kurzy module with courses, participants, and registrations management
- Add project documents and service documents features
- Add service folders for document organization
- Add SQL import queries for services from firmy.slovensko.ai
- Update todo notifications and group messaging
- Various API improvements and bug fixes

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/db/migrations/0005_add_service_folders_documents.sql

@@ -0,0 +1,26 @@
+-- Create service_folders table
+CREATE TABLE IF NOT EXISTS service_folders (
+  id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
+  name TEXT NOT NULL,
+  created_by UUID REFERENCES users(id) ON DELETE SET NULL,
+  created_at TIMESTAMP DEFAULT NOW() NOT NULL,
+  updated_at TIMESTAMP DEFAULT NOW() NOT NULL
+);
+
+-- Create service_documents table
+CREATE TABLE IF NOT EXISTS service_documents (
+  id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
+  folder_id UUID NOT NULL REFERENCES service_folders(id) ON DELETE CASCADE,
+  file_name TEXT NOT NULL,
+  original_name TEXT NOT NULL,
+  file_path TEXT NOT NULL,
+  file_type TEXT NOT NULL,
+  file_size INTEGER NOT NULL,
+  description TEXT,
+  uploaded_by UUID REFERENCES users(id) ON DELETE SET NULL,
+  uploaded_at TIMESTAMP DEFAULT NOW() NOT NULL,
+  created_at TIMESTAMP DEFAULT NOW() NOT NULL
+);
+
+-- Create indexes for faster lookups
+CREATE INDEX IF NOT EXISTS idx_service_documents_folder_id ON service_documents(folder_id);