requests: guard against getaddrinfo() hang when WiFi not connected

Summary

The request() function in requests/__init__.py calls socket.getaddrinfo() (line 81) without verifying network connectivity. On platforms where getaddrinfo() blocks indefinitely when the WiFi interface is active but not connected (see micropython/micropython#18797), this causes the device to freeze with no way to recover except a hard reset.

The timeout parameter passed to requests.get() has no effect because socket.settimeout() is applied to the socket object (line 93) — which is created after getaddrinfo() returns. So the hang occurs before any timeout takes effect.

Suggested fix

Add a connectivity check before getaddrinfo():

    # Guard: getaddrinfo() blocks indefinitely on RP2040/RP2350 when the
    # CYW43 WiFi interface is active but has no IP address.
    try:
        import network
        _wlan = network.WLAN(network.STA_IF)
        if not _wlan.isconnected():
            raise OSError(-1, "WiFi not connected")
    except ImportError:
        pass  # Non-WiFi platform, skip guard

    ai = socket.getaddrinfo(host, port, 0, socket.SOCK_STREAM)

This is wrapped in try/except ImportError so it's safe on non-WiFi platforms (ESP32 Ethernet, Unix port, etc.).

Also consider

A default socket timeout (e.g., 30s) applied before getaddrinfo() would provide defense-in-depth, though it wouldn't help here since settimeout() only affects socket operations, not DNS resolution.

Environment

• Board: Raspberry Pi Pico 2 W (RP2350 + CYW43)
• MicroPython: v1.26.1
• Upstream issue: micropython/micropython#18797

Start in requests/init.py at request(), especially the socket.getaddrinfo() call around line 81 and socket timeout setup around line 93. Reproduce or review the RP2040/RP2350 WiFi case, then verify that disconnected WiFi no longer hangs, while non-WiFi platforms continue past the guard; the issue names no test file.