Summary

• Tool output (MCP): Extract text from API content blocks ([{"type":"text","text":"..."}]) instead of stringifying the raw wrapper array
• Tool input (MCP): Render inputs as key-value pairs instead of raw JSON.stringify — string values display directly (preserving real newlines)
• Pretty-print extracted text when it's valid JSON
• Preserves existing behavior for plain string outputs and specialized tool viewers (Edit, Bash, Read, etc.)

Closes #32

Testing

• npm run typecheck passes
• npm test passes
• npm run lint passes
• Added tests in test/renderer/utils/renderHelpers.test.ts covering:
  • extractOutputText: plain strings, JSON pretty-printing, content block arrays,
    serialized content block arrays, multiple blocks joined with newlines
  • formatInputValue: strings returned directly (preserving newlines), numbers/booleans
    converted with String(), objects/arrays pretty-printed with JSON.stringify