huge refactor of the entire codebase, with the goal of improving maintainability, readability, and extensibility. This commit includes changes to almost every file in the project, including:

TUI/modalscreen/search.py

@@ -16,7 +16,7 @@ import asyncio
 sys.path.insert(0, str(Path(__file__).parent.parent))
 from SYS.config import load_config, resolve_output_dir
 from SYS.result_table import Table
-from ProviderCore.registry import get_search_provider
+from ProviderCore.registry import get_search_plugin
 
 logger = logging.getLogger(__name__)
 
@@ -174,7 +174,7 @@ class SearchModal(ModalScreen):
             self.current_worker.log_step(f"Connecting to {source}...")
 
         try:
-            provider = get_search_provider(source)
+            provider = get_search_plugin(source)
             if not provider:
                 logger.error(f"[search-modal] Provider not available: {source}")
                 if self.current_worker:
@@ -380,7 +380,7 @@ class SearchModal(ModalScreen):
             config = load_config()
             output_dir = resolve_output_dir(config)
 
-            provider = get_search_provider("openlibrary", config=config)
+            provider = get_search_plugin("openlibrary", config=config)
             if not provider:
                 logger.error("[search-modal] Provider not available: openlibrary")
                 return