Fix WiFi detection when wired connection is primary

[CrazyTodd-one]

Summary

Fixes #1775 — When a laptop is connected via both WiFi and a wired connection (e.g. docking station), the primary connection is wired. get_current_wifi() only checked the primary connection, so the WiFi SSID was never detected and network-based backup restrictions were silently bypassed.

Changes:

• get_current_wifi() now iterates all active NetworkManager connections instead of only the primary one
• Added get_active_connections_paths() to the DBus adapter, reading the ActiveConnections property
• Per-connection DBus failures are handled gracefully (logged and skipped, other connections still checked)

Test plan

• Added test_get_current_wifi_with_wired_primary_and_wifi_active — simulates the docking station scenario (wired primary + WiFi active), verifies WiFi SSID is found
• Added test_get_current_wifi_skips_failed_connection — verifies that if one connection throws DBusException, remaining connections are still checked
• Updated existing tests to use get_active_connections_paths mock
• Fixed incorrect 802-11-ethernet type string to 802-3-ethernet in parametrized test

[m3nu]

Clean, focused fix for a long-standing issue (#1775). The approach of iterating all active connections instead of only the primary is correct and well-implemented.

Strengths:

• Reuses existing read_dbus_property() helper -- consistent with the adapter pattern
• Per-connection DBusException handling so one failure doesn't block checking others
• Two good new tests covering the wired+wifi scenario and per-connection failure resilience
• Fixes pre-existing 802-11-ethernet → 802-3-ethernet typo in test data
• API contract preserved (get_current_wifi() -> str | None)

Note: competing PR #2473 addresses the same issue but has significant problems (debug prints in production, deletes metered-network check, catches bare Exception, no tests, breaks ABC contract). Recommend closing it in favor of this one.