fix: avoid mutating redirect chain array when formatting

[AI-Reviewer-QS]

Summary

• toStringDetailed() and toJSONDetailed() call .reverse() on the array returned by request.redirectChain(), which mutates the original array in-place
• Subsequent calls to these methods or any code that reads the redirect chain will see the reversed (incorrect) order
• Fixed by copying the array with spread syntax before reversing: [...redirectChain].reverse()

Reproduction

const formatter = new NetworkFormatter(request, options);

// First call: redirect chain is [A -> B -> C], reversed to [C, B, A] ✓
formatter.toStringDetailed();

// Second call: chain is now [C, B, A] (mutated), reversed again to [A, B, C] ✗
formatter.toStringDetailed(); // Shows wrong order

Test plan

• Verify redirect chain displays in correct order on first call
• Verify redirect chain displays in correct order on repeated calls
• Verify both toStringDetailed() and toJSONDetailed() produce consistent output

[OrKoN]

The underlying implementation in Puppeteer is:

override redirectChain(): CdpHTTPRequest[] {
    return this._redirectChain.slice();
  }

which already creates a copy.

[OrKoN]

cc @nroscino