fix: search all lines for HP banner, not just first line

Old ProCurve show version starts with "Image stamp:" — the HP product
banner (e.g. "HP J9298A Switch 2520G-8-PoE") appears on a later line.
Scan all lines and use the first HP/HPE/Aruba banner found.

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

napalm_procurve/parsers.py

@@ -199,13 +199,16 @@ def parse_model_from_version(output: str) -> tuple[str, str]:
     Returns ("", "") when the first line is not an HP/Aruba device banner
     (e.g. when show version starts with "Image stamp:" on newer Aruba).
     """
-    first = output.strip().splitlines()[0] if output.strip() else ""
-    if not first:
-        return "", ""
-
-    # Only process lines that start with an HP/Aruba product banner
-    if not re.match(r"\s*(?:HP|HPE|Aruba)\b", first, re.I):
+    # Find the HP/Aruba product banner line — may not be the first line
+    # (older ProCurve shows "Image stamp:" first, banner follows later)
+    banner = ""
+    for line in output.splitlines():
+        if re.match(r"\s*(?:HP|HPE|Aruba)\b", line, re.I):
+            banner = line.strip()
+            break
+    if not banner:
         return "", ""
+    first = banner
 
     # Extract J-code part number
     _PN_RE_V = re.compile(r"\b(J\d{4}[A-Z]{1,2})\b")