refactor(mocks): add as const satisfies to all mock tool definitions

Applied 'as const satisfies McpToolDefinition[]' pattern consistently
across all mock tool definitions (defaultMcpTools, accountMcpTools,
mixedProviderTools) for improved type safety and immutability.

This ensures TypeScript can infer the most specific literal types
whilst maintaining type compatibility, following the project's
typescript-patterns skill guidelines.

Author: ryoppippi

mocks/mcp-server.ts

@@ -96,7 +96,7 @@ export function createMcpApp(options: MockMcpServerOptions): HonoApp {
 
 // Pre-defined tool sets for common test scenarios
 
-export const defaultMcpTools: McpToolDefinition[] = [
+export const defaultMcpTools = [
   {
     name: 'default_tool_1',
     description: 'Default Tool 1',
@@ -114,9 +114,9 @@ export const defaultMcpTools: McpToolDefinition[] = [
       required: ['id'],
     },
   },
-];
+] as const satisfies McpToolDefinition[];
 
-export const accountMcpTools: Record<string, McpToolDefinition[]> = {
+export const accountMcpTools = {
   acc1: [
     {
       name: 'acc1_tool_1',
@@ -135,7 +135,7 @@ export const accountMcpTools: Record<string, McpToolDefinition[]> = {
         required: ['id'],
       },
     },
-  ],
+  ] as const satisfies McpToolDefinition[],
   acc2: [
     {
       name: 'acc2_tool_1',
@@ -154,7 +154,7 @@ export const accountMcpTools: Record<string, McpToolDefinition[]> = {
         required: ['id'],
       },
     },
-  ],
+  ] as const satisfies McpToolDefinition[],
   acc3: [
     {
       name: 'acc3_tool_1',
@@ -164,7 +164,7 @@ export const accountMcpTools: Record<string, McpToolDefinition[]> = {
         properties: { fields: { type: 'string' } },
       },
     },
-  ],
+  ] as const satisfies McpToolDefinition[],
   'test-account': [
     {
       name: 'dummy_action',
@@ -181,8 +181,8 @@ export const accountMcpTools: Record<string, McpToolDefinition[]> = {
         additionalProperties: false,
       },
     },
-  ],
-};
+  ] as const satisfies McpToolDefinition[],
+} as const;
 
 export const mixedProviderTools = [
   {