feat: Implement modular plugin architecture

- Convert invcount to self-contained module
- Add Module Manager for install/uninstall
- Create module_registry database table
- Support hot-reloading of modules
- Move data imports into invcount module
- Update all templates and routes to new structure

Version bumped to 0.16.0

app.py

@@ -1,7 +1,7 @@
 """
-ScanLook - Inventory Management System
+ScanLook - Modular Inventory Management System
 Flask Application
-Production-Ready Release
+Production-Ready Release with Module System
 """
 from flask import Flask, render_template, request, redirect, url_for, session, flash, jsonify, send_from_directory
 from werkzeug.security import check_password_hash
@@ -13,21 +13,11 @@ app = Flask(__name__)
 
 # Now import your custom modules
 from db import query_db, execute_db, get_db
-from blueprints.data_imports import data_imports_bp
 from blueprints.users import users_bp
-from blueprints.sessions import sessions_bp
-from blueprints.admin_locations import admin_locations_bp
-from blueprints.counting import counting_bp  
-from blueprints.cons_sheets import cons_sheets_bp
 from utils import login_required
 
-# Register Blueprints
-app.register_blueprint(data_imports_bp)
+# Register Core Blueprints (non-modular)
 app.register_blueprint(users_bp)
-app.register_blueprint(sessions_bp)
-app.register_blueprint(admin_locations_bp)
-app.register_blueprint(counting_bp)          
-app.register_blueprint(cons_sheets_bp)
 
 # V1.0: Use environment variable for production, fallback to demo key for development
 app.secret_key = os.environ.get('SCANLOOK_SECRET_KEY', 'scanlook-demo-key-replace-for-production')
@@ -38,7 +28,7 @@ app.config['PERMANENT_SESSION_LIFETIME'] = timedelta(hours=1)
 
 
 # 1. Define the version
-APP_VERSION = '0.15.0'
+APP_VERSION = '0.16.0'  # Bumped version for modular architecture
 
 # 2. Inject it into all templates automatically
 @app.context_processor
@@ -53,11 +43,17 @@ if not os.path.exists(db_path):
     init_database()
     create_default_users()
     print("Database initialized!")
+    print("📦 Install modules from /admin/modules")
 
 # Run migrations to apply any pending database changes
 from migrations import run_migrations
 run_migrations()
 
+# Load and register active modules
+from module_manager import get_module_manager
+module_manager = get_module_manager()
+module_manager.load_active_modules(app)
+
 
 # ==================== ROUTES: AUTHENTICATION ====================
 
@@ -119,49 +115,124 @@ def home():
     return render_template('home.html', modules=modules)
 
 
-# ==================== ROUTES: DASHBOARD ====================
+# ==================== ROUTES: ADMIN DASHBOARD ====================
 
 @app.route('/admin')
 @login_required
 def admin_dashboard():
-    """Main dashboard - different views for admin vs staff"""
+    """Admin dashboard - shows all available modules"""
     role = session.get('role')
     
-    if role in ['owner', 'admin']:
-        # Admin dashboard
-        show_archived = request.args.get('show_archived', '0') == '1'
-        
-        if show_archived:
-            # Show all sessions (active and archived)
-            sessions_list = query_db('''
-                SELECT s.*, u.full_name as created_by_name,
-                       COUNT(DISTINCT lc.location_count_id) as total_locations,
-                       SUM(CASE WHEN lc.status = 'completed' THEN 1 ELSE 0 END) as completed_locations,
-                       SUM(CASE WHEN lc.status = 'in_progress' THEN 1 ELSE 0 END) as in_progress_locations
-                FROM CountSessions s
-                LEFT JOIN Users u ON s.created_by = u.user_id
-                LEFT JOIN LocationCounts lc ON s.session_id = lc.session_id
-                WHERE s.status IN ('active', 'archived')
-                GROUP BY s.session_id
-                ORDER BY s.status ASC, s.created_timestamp DESC
-            ''')
-        else:
-            # Show only active sessions
-            sessions_list = query_db('''
-                SELECT s.*, u.full_name as created_by_name,
-                       COUNT(DISTINCT lc.location_count_id) as total_locations,
-                       SUM(CASE WHEN lc.status = 'completed' THEN 1 ELSE 0 END) as completed_locations,
-                       SUM(CASE WHEN lc.status = 'in_progress' THEN 1 ELSE 0 END) as in_progress_locations
-                FROM CountSessions s
-                LEFT JOIN Users u ON s.created_by = u.user_id
-                LEFT JOIN LocationCounts lc ON s.session_id = lc.session_id
-                WHERE s.status = 'active'
-                GROUP BY s.session_id
-                ORDER BY s.created_timestamp DESC
-            ''')
-        
-        return render_template('admin_dashboard.html', sessions=sessions_list, show_archived=show_archived)
+    if role not in ['owner', 'admin']:
+        flash('Access denied. Admin role required.', 'danger')
+        return redirect(url_for('home'))
+    
+    # Get modules this user has access to
+    user_id = session.get('user_id')
+    modules = query_db('''
+        SELECT m.module_id, m.module_name, m.module_key, m.description, m.icon
+        FROM Modules m
+        JOIN UserModules um ON m.module_id = um.module_id
+        WHERE um.user_id = ? AND m.is_active = 1
+        ORDER BY m.display_order
+    ''', [user_id])
+    
+    return render_template('admin_dashboard.html', modules=modules)
 
+# ==================== MODULE MANAGER UI ====================
+
+@app.route('/admin/modules')
+@login_required
+def module_manager_ui():
+    """Module manager interface for admins"""
+    if session.get('role') not in ['owner', 'admin']:
+        flash('Access denied. Admin role required.', 'danger')
+        return redirect(url_for('home'))
+    
+    modules = module_manager.scan_available_modules()
+    return render_template('module_manager.html', modules=modules)
+
+
+@app.route('/admin/modules/<module_key>/install', methods=['POST'])
+@login_required
+def install_module(module_key):
+    """Install a module"""
+    if session.get('role') not in ['owner', 'admin']:
+        return jsonify({'success': False, 'message': 'Access denied'}), 403
+    
+    result = module_manager.install_module(module_key)
+    
+    # Hot-reload: Register the blueprint immediately if installation succeeded
+    if result['success']:
+        try:
+            from pathlib import Path
+            import importlib.util
+            import sys
+            
+            module = module_manager.get_module_by_key(module_key)
+            if module:
+                init_path = Path(module['path']) / '__init__.py'
+                
+                # Import the module
+                spec = importlib.util.spec_from_file_location(
+                    f"modules.{module_key}", 
+                    init_path
+                )
+                module_package = importlib.util.module_from_spec(spec)
+                sys.modules[spec.name] = module_package
+                spec.loader.exec_module(module_package)
+                
+                # Create and register blueprint
+                if hasattr(module_package, 'create_blueprint'):
+                    blueprint = module_package.create_blueprint()
+                    app.register_blueprint(blueprint)
+                    print(f"🔥 Hot-loaded: {module['name']} at {module.get('routes_prefix')}")
+                    result['message'] += ' (Module loaded - no restart needed!)'
+                else:
+                    print(f"⚠️  Module {module_key} missing create_blueprint()")
+                    result['message'] += ' (Restart required - missing create_blueprint)'
+            else:
+                print(f"⚠️  Could not find module {module_key} after installation")
+                result['message'] += ' (Restart required - module not found)'
+        except Exception as e:
+            print(f"❌ Hot-reload failed for {module_key}: {e}")
+            import traceback
+            traceback.print_exc()
+            result['message'] += f' (Restart required - hot-reload failed)'
+    
+    return jsonify(result)
+
+@app.route('/admin/modules/<module_key>/uninstall', methods=['POST'])
+@login_required
+def uninstall_module(module_key):
+    """Uninstall a module"""
+    if session.get('role') not in ['owner', 'admin']:
+        return jsonify({'success': False, 'message': 'Access denied'}), 403
+    
+    result = module_manager.uninstall_module(module_key, drop_tables=True)
+    return jsonify(result)
+
+
+@app.route('/admin/modules/<module_key>/activate', methods=['POST'])
+@login_required
+def activate_module(module_key):
+    """Activate a module"""
+    if session.get('role') not in ['owner', 'admin']:
+        return jsonify({'success': False, 'message': 'Access denied'}), 403
+    
+    result = module_manager.activate_module(module_key)
+    return jsonify(result)
+
+
+@app.route('/admin/modules/<module_key>/deactivate', methods=['POST'])
+@login_required
+def deactivate_module(module_key):
+    """Deactivate a module"""
+    if session.get('role') not in ['owner', 'admin']:
+        return jsonify({'success': False, 'message': 'Access denied'}), 403
+    
+    result = module_manager.deactivate_module(module_key)
+    return jsonify(result)
 
 
 # ==================== PWA SUPPORT ROUTES ====================
@@ -204,6 +275,19 @@ def whatami():
     """
 
 
+@app.route('/debug/routes')
+@login_required
+def list_routes():
+    """Debug: List all registered routes"""
+    if session.get('role') not in ['owner', 'admin']:
+        return "Access denied", 403
+    
+    routes = []
+    for rule in app.url_map.iter_rules():
+        routes.append(f"{rule.endpoint}: {rule.rule}")
+    
+    return "<br>".join(sorted(routes))
+
 # ==================== RUN APPLICATION ====================
 
 if __name__ == '__main__':