feat: Add zap command for sending Bitcoin Lightning tips

- Implemented the `zap` command in the CLI to allow users to send sats to a user, event, or snippet using a NIP-60 wallet.
- Created a new `zap.ts` file to handle the command logic and integrated it into the MCP server.
- Added wallet balance command to check the balance of a user's wallet.
- Enhanced the MCP server to register the new zap command and wallet balance command.
- Introduced caching for wallets to optimize performance and reduce redundant network requests.
- Updated database schema to include snippets table for storing code snippets.
- Improved logging functionality for better debugging and tracking of operations.
- Added functionality to save snippets to the database upon retrieval.
- Updated project overview documentation to reflect new features and structure.
- Refactored existing commands and logic for better modularity and maintainability.

logic/list_usernames.ts

@@ -55,12 +55,7 @@ export function addListUsernamesCommand(server: McpServer) {
     server.tool(
         "list_usernames",
         "List all available usernames in the system",
-        {
-            random_string: z
-                .string()
-                .optional()
-                .describe("Dummy parameter for no-parameter tools"),
-        },
+        { },
         async () => {
             return listUsernames();
         }