fix: make FuzzySearch generic to support typed items

- Add SearchableItem base interface for minimum required fields
- Make FuzzySearch class generic with type parameter
- Update all page scripts to use typed FuzzySearch instances
- Fix type casting in calculateScore method

website/src/scripts/pages/prompts.ts

@@ -22,7 +22,7 @@ interface PromptsData {
 
 const resourceType = 'prompt';
 let allItems: Prompt[] = [];
-let search = new FuzzySearch();
+let search = new FuzzySearch<Prompt>();
 let toolSelect: Choices;
 let currentFilters = { tools: [] as string[] };