fix: support paginated tool discovery and avoid info instruction timeouts

[haosenwang1018]

Fixes #206

What

• make listTools() follow nextCursor and aggregate all pages
• add a regression test for multi-page tool listings
• make info <server> treat getInstructions() as best-effort so a slow/unsupported instructions fetch does not fail or time out the whole command

Why

Some MCP servers expose tools across multiple pages. The previous implementation only returned the first page, which could make tools appear missing.

While validating that fix, I also hit an HTTP integration timeout caused by info eagerly waiting on getInstructions() even though the core server details output does not require it. Making instructions optional keeps the command responsive without affecting the main details view.

Testing

• bun test tests/integration/cli.test.ts tests/cli-errors.test.ts
• result: 68 pass / 0 fail