feat: add slug-only dashboard profile filter and unify backend imports

backend/src/core/plugin_loader.py

@@ -76,17 +76,8 @@ class PluginLoader:
             """
             Loads a single Python module and extracts PluginBase subclasses.
             """
-        # Try to determine the correct package prefix based on how the app is running
-        # For standalone execution, we need to handle the import differently
-        if __name__ == "__main__" or "test" in __name__:
-            # When running as standalone or in tests, use relative import
-            package_name = f"plugins.{module_name}"
-        elif "backend.src" in __name__:
-            package_prefix = "backend.src.plugins"
-            package_name = f"{package_prefix}.{module_name}"
-        else:
-            package_prefix = "src.plugins"
-            package_name = f"{package_prefix}.{module_name}"
+        # All runtime code is imported through the canonical `src` package root.
+        package_name = f"src.plugins.{module_name}"
             
         # print(f"DEBUG: Loading plugin {module_name} as {package_name}")
         spec = importlib.util.spec_from_file_location(package_name, file_path)
@@ -198,4 +189,4 @@ class PluginLoader:
         return plugin_id in self._plugins
     # [/DEF:has_plugin:Function]
 
-# [/DEF:PluginLoader:Class]
+# [/DEF:PluginLoader:Class]