fix: fix_snmp SSH fallback when driver is connected via REST API

The REST API has no writable config endpoint for SNMP communities.
When _action_fix_snmp() is called on a REST-connected driver, it now
opens a temporary Netmiko SSH session (standard KEX, then legacy KEX
fallback), runs the config-mode CLI commands, and restores the REST
transport state on exit. SSH errors are surfaced verbatim instead of
being silently swallowed.

Also:
- _save_config: guard against REST transport (was calling self._device
  directly → NoneType AttributeError when transport == "api")
- _action_fix_snmp: extracted CLI logic into _action_fix_snmp_cli()
  so it is reused for both the SSH-fallback and native SSH/Telnet paths
- api_client: add get_snmp_communities() + configure_snmp_community()
  for future use; improve GET error logging (warn vs debug on non-404)
- _try_api: probe timeout capped at 15 s; SSL retry loop for
  self-signed certificates; improved log levels
- _api_set_interface / _cli_set_interface: handle enabled/description
  fields that were previously ignored
- probe(): broaden accepted status codes (301/302/303/403)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

napalm_procurve/api_client.py

@@ -79,7 +79,9 @@ class ProcurveApiClient:
                     # 401 = API exists but not authenticated  (most common)
                     # 200 = API exists and accessible without auth (unusual)
                     # 405 = wrong HTTP verb but API is there
-                    if resp.status_code in (200, 401, 405):
+                    # 302/301/303 = redirect to login page (older firmware)
+                    # 403 = API exists but access forbidden
+                    if resp.status_code in (200, 301, 302, 303, 401, 403, 405):
                         logger.debug(
                             "API detected at %s (HTTP %s, %s %s)",
                             hostname, resp.status_code, proto, ver,
@@ -169,9 +171,12 @@ class ProcurveApiClient:
             resp = self._session.get(url, timeout=self.timeout)
             if resp.ok:
                 return resp.json()
-            logger.debug("GET %s returned HTTP %s", url, resp.status_code)
+            if resp.status_code == 404:
+                logger.debug("GET %s returned HTTP 404", url)
+            else:
+                logger.warning("GET %s returned HTTP %s: %s", url, resp.status_code, resp.text[:200])
         except Exception as exc:
-            logger.debug("GET %s error: %s", url, exc)
+            logger.warning("GET %s error: %s", url, exc)
         return {}
 
     def post(self, endpoint: str, **kwargs: Any) -> requests.Response:
@@ -481,6 +486,36 @@ class ProcurveApiClient:
                 f"delete_vlan({vlan_id}): REST API returned HTTP {resp.status_code}"
             )
 
+    def get_snmp_communities(self) -> Dict[str, Dict]:
+        """Return configured SNMP communities from REST API."""
+        data = self.get("snmp-server/community")
+        result: Dict[str, Dict] = {}
+        for entry in data.get("snmp_community_element", []):
+            name = entry.get("community_name", "")
+            if name:
+                result[name] = {"access_type": entry.get("access_type", "")}
+        return result
+
+    def configure_snmp_community(self, community: str = "public") -> Tuple[bool, str]:
+        """Ensure an SNMP read-only community exists via REST resource endpoint.
+
+        Returns (success, message).
+        """
+        existing = self.get_snmp_communities()
+        if community in existing:
+            return True, f"SNMP community '{community}' already exists."
+
+        resp = self.post("snmp-server/community", json={
+            "community_name": community,
+            "access_type": "MIB2",
+        })
+        if resp.ok:
+            return True, f"SNMP community '{community}' configured via REST API."
+        if resp.status_code == 409:
+            return True, f"SNMP community '{community}' already exists."
+
+        return False, f"REST API returned HTTP {resp.status_code}: {resp.text[:200]}"
+
     def ping(
         self,
         destination: str,