feat: name only a missing base64; lldpd, auc and updates are facts (0.3.0)

get_device_warnings no longer names lldpd_not_installed,
updates_available or update_notifications_disabled. The packages and
get_available_updates are the facts; netOrk derives the warnings with the
same reach (netOrk #1111). The old update read swallowed failures,
get_available_updates raises them.

no_base64 stays: BusyBox may provide base64 as an applet, so no package
tells the caller whether it is there.

tests/unit/test_warnings.py

@@ -0,0 +1,43 @@
+"""What the driver still names itself (netOrk #1111).
+
+lldpd, auc and the pending updates are facts the caller reads (``get_packages``,
+``get_available_updates``) and decides on. A missing ``base64`` stays: BusyBox
+may provide it as an applet, so no package says whether it is there.
+"""
+
+from __future__ import annotations
+
+from napalm_openwrt import OpenWrtDriver
+
+
+def _driver(answers: dict[str, str]) -> OpenWrtDriver:
+    d = OpenWrtDriver("ap", "root", "pw")
+    issued: list[str] = []
+
+    def send(command: str) -> str:
+        issued.append(command)
+        return next((out for frag, out in answers.items() if frag in command), "")
+
+    d._send_command = send
+    d.issued = issued
+    return d
+
+
+def test_nothing_installed_names_only_base64():
+    """No lldpd, no auc and an opkg system: the caller names those from the packages."""
+    d = _driver({"opkg list-upgradable": "luci - 1.0 - 1.1\n"})
+
+    assert [w["code"] for w in d.get_device_warnings()] == ["no_base64"]
+
+
+def test_base64_present_names_nothing():
+    d = _driver({"command -v base64": "/usr/bin/base64\n"})
+
+    assert d.get_device_warnings() == []
+
+
+def test_one_command_per_poll():
+    d = _driver({})
+    d.get_device_warnings()
+
+    assert d.issued == ["command -v base64 2>/dev/null"]