fix: stop false-positive [hardware] tickets in a redundant Ceph fleet

Two monitoring-logic fixes so hwmonDaemon stops raising spurious hardware
tickets on a Ceph-backed cluster with PBS backups:

- _check_system_drive_indicators: count dmesg Buffer I/O / block errors
  per-line and skip non-physical / network-backed devices (Ceph RBD, dm-,
  loop). RBD Buffer I/O errors are storage-connectivity events (e.g. a Ceph
  mon-session blip), not local drive faults, so they must not raise a
  CRITICAL drive alert. Consistent with the existing _is_physical_disk
  exclusion. (Fired a false "CRITICAL: Buffer I/O errors (75 occurrences)"
  ticket where all 75 were on rbd devices.)

- _get_attribute_thresholds: drop the Power_On_Hours warning/critical
  threshold. Drive age alone is not a failure; with 2-3x Ceph redundancy
  and PBS backups we run drives to hard-failure rather than replace on age.
  The value is still recorded (history/description/new-drive logic) but no
  longer generates a ticket. Real failure-predictors (reallocated/pending/
  uncorrectable/CRC, self-test, trends) are unchanged.

Adds 7 regression tests (TestSystemDriveIndicators, TestAttributeThresholds).
All 98 tests pass; flake8 clean.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

hwmonDaemon.py

@@ -1296,10 +1296,20 @@ class SystemHealthMonitor:
                     (r'nvme\d+.*I/O error', 'NVMe I/O errors')
                 ]
 
+                # Kernel-log references to non-physical / network-backed block devices.
+                # Errors on these are NOT local hardware faults: e.g. "Buffer I/O error on
+                # dev rbdN" is caused by Ceph connectivity blips, not a failing drive. Ceph
+                # RBD is likewise excluded from physical-disk monitoring (see _is_physical_disk).
+                non_physical_dev = re.compile(r'\b(?:rbd\d+|dm-\d+|loop\d+)\b', re.IGNORECASE)
+
                 for pattern, description in error_patterns:
-                    matches = re.findall(pattern, result.stdout, re.IGNORECASE)
-                    if matches:
-                        count = len(matches)
+                    compiled = re.compile(pattern, re.IGNORECASE)
+                    # Count matching lines, skipping those for non-physical devices.
+                    count = sum(
+                        1 for line in result.stdout.splitlines()
+                        if compiled.search(line) and not non_physical_dev.search(line)
+                    )
+                    if count:
                         if count >= 5:
                             system_health['status'] = 'CRITICAL'
                             system_health['issues'].append(f"CRITICAL: {description} in system logs ({count} occurrences)")
@@ -2610,7 +2620,11 @@ class SystemHealthMonitor:
             'Reported_Uncorrect': {'warning': 1, 'critical': 10},
             'Spin_Retry_Count': {'warning': 1, 'critical': 5},
             'Power_Cycle_Count': {'warning': 5000, 'critical': 10000},
-            'Power_On_Hours': {'warning': 61320, 'critical': 70080},
+            # Power_On_Hours (drive age) intentionally has NO threshold: age alone is not a
+            # failure and we run drives to hard-failure rather than replace on age. With Ceph
+            # (2-3x redundancy) + PBS backups, a dead drive just drops an OSD and self-heals.
+            # The value is still recorded (attributes/history/description); only real
+            # failure-predictors (reallocated/pending/uncorrectable/CRC, self-test) raise tickets.
             'Temperature_Celsius': {'warning': 65, 'critical': 75},
             'Available_Spare': {'warning': 30, 'critical': 10},
             'Program_Fail_Count': {'warning': 10, 'critical': 20},