fix: env overrides and OS-aware test improvements

- Add PBS/PMG polling interval environment variable overrides in config.go
- Fix temp path expectation in detect_root_test.go using filepath.Join
- Use EvalSymlinks for symlink target comparison in self_update_test.go
- Add Linux-only skip for MAC fallback test in agent_new_test.go
- Add OS-aware RAID/SMART assertions in agent_metrics_test.go

internal/config/config.go

@@ -830,6 +830,50 @@ func Load() (*Config, error) {
 		}
 	}
 
+	if intervalStr := utils.GetenvTrim("PBS_POLLING_INTERVAL"); intervalStr != "" {
+		if dur, err := time.ParseDuration(intervalStr); err == nil {
+			if dur < 10*time.Second {
+				log.Warn().Dur("interval", dur).Msg("Ignoring PBS_POLLING_INTERVAL below 10s from environment")
+			} else {
+				cfg.PBSPollingInterval = dur
+				cfg.EnvOverrides["PBS_POLLING_INTERVAL"] = true
+				log.Info().Dur("interval", dur).Msg("Overriding PBS polling interval from environment")
+			}
+		} else if seconds, err := strconv.Atoi(intervalStr); err == nil {
+			if seconds < 10 {
+				log.Warn().Int("seconds", seconds).Msg("Ignoring PBS_POLLING_INTERVAL below 10s from environment")
+			} else {
+				cfg.PBSPollingInterval = time.Duration(seconds) * time.Second
+				cfg.EnvOverrides["PBS_POLLING_INTERVAL"] = true
+				log.Info().Int("seconds", seconds).Msg("Overriding PBS polling interval (seconds) from environment")
+			}
+		} else {
+			log.Warn().Str("value", intervalStr).Msg("Invalid PBS_POLLING_INTERVAL value, expected duration or seconds")
+		}
+	}
+
+	if intervalStr := utils.GetenvTrim("PMG_POLLING_INTERVAL"); intervalStr != "" {
+		if dur, err := time.ParseDuration(intervalStr); err == nil {
+			if dur < 10*time.Second {
+				log.Warn().Dur("interval", dur).Msg("Ignoring PMG_POLLING_INTERVAL below 10s from environment")
+			} else {
+				cfg.PMGPollingInterval = dur
+				cfg.EnvOverrides["PMG_POLLING_INTERVAL"] = true
+				log.Info().Dur("interval", dur).Msg("Overriding PMG polling interval from environment")
+			}
+		} else if seconds, err := strconv.Atoi(intervalStr); err == nil {
+			if seconds < 10 {
+				log.Warn().Int("seconds", seconds).Msg("Ignoring PMG_POLLING_INTERVAL below 10s from environment")
+			} else {
+				cfg.PMGPollingInterval = time.Duration(seconds) * time.Second
+				cfg.EnvOverrides["PMG_POLLING_INTERVAL"] = true
+				log.Info().Int("seconds", seconds).Msg("Overriding PMG polling interval (seconds) from environment")
+			}
+		} else {
+			log.Warn().Str("value", intervalStr).Msg("Invalid PMG_POLLING_INTERVAL value, expected duration or seconds")
+		}
+	}
+
 	if enabledStr := utils.GetenvTrim("ENABLE_TEMPERATURE_MONITORING"); enabledStr != "" {
 		if enabled, err := strconv.ParseBool(enabledStr); err == nil {
 			cfg.TemperatureMonitoringEnabled = enabled

internal/config/detect_root_test.go

@@ -2,6 +2,7 @@ package config
 
 import (
 	"os"
+	"path/filepath"
 	"testing"
 )
 
@@ -93,7 +94,7 @@ func TestDetectAppRoot_Scenarios(t *testing.T) {
 			name:           "Executable in temp, getwd error",
 			mockExec:       os.TempDir() + "/go-build123/exe",
 			mockGetwdErr:   os.ErrPermission,
-			expectedResult: os.TempDir() + "/go-build123", // Falls back to exe dir
+			expectedResult: filepath.Join(os.TempDir(), "go-build123"), // Falls back to exe dir
 		},
 		{
 			name:           "Executable error, getwd error",

internal/dockeragent/self_update_test.go

@@ -99,8 +99,12 @@ func TestResolveSymlink(t *testing.T) {
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
-	if got != target {
-		t.Fatalf("expected %q, got %q", target, got)
+	expected, err := filepath.EvalSymlinks(target)
+	if err != nil {
+		t.Fatalf("eval symlinks target: %v", err)
+	}
+	if got != expected {
+		t.Fatalf("expected %q, got %q", expected, got)
 	}
 
 	if _, err := resolveSymlink(filepath.Join(dir, "missing")); err == nil {

internal/hostagent/agent_metrics_test.go

@@ -3,6 +3,7 @@ package hostagent
 import (
 	"context"
 	"errors"
+	"runtime"
 	"testing"
 	"time"
 
@@ -184,6 +185,12 @@ func TestBuildReport(t *testing.T) {
 			t.Fatalf("buildReport failed: %v", err)
 		}
 
+		if runtime.GOOS != "linux" {
+			if len(report.RAID) != 0 {
+				t.Errorf("Expected no RAID arrays on %s, got %d", runtime.GOOS, len(report.RAID))
+			}
+			return
+		}
 		if len(report.RAID) != 1 {
 			t.Errorf("Expected 1 RAID array, got %d", len(report.RAID))
 		} else if report.RAID[0].Name != "md0" {
@@ -270,6 +277,12 @@ func TestBuildReport(t *testing.T) {
 		}
 
 		// SMART data is attached to Sensors in the report
+		if runtime.GOOS != "linux" {
+			if len(report.Sensors.SMART) != 0 {
+				t.Errorf("Expected no SMART disks on %s, got %d", runtime.GOOS, len(report.Sensors.SMART))
+			}
+			return
+		}
 		if len(report.Sensors.SMART) != 1 {
 			t.Errorf("Expected 1 SMART disk, got %d", len(report.Sensors.SMART))
 		} else {

internal/hostagent/agent_new_test.go

@@ -172,6 +172,10 @@ func TestNew_FallsBackToHostnameWhenMachineIDAndMACEmpty(t *testing.T) {
 }
 
 func TestNew_FallsBackToMACWhenMachineIDEmpty(t *testing.T) {
+	if runtime.GOOS != "linux" {
+		t.Skip("MAC fallback is Linux-only")
+	}
+
 	originalHostInfo := hostInfoWithContext
 	originalReadFile := readFile
 	originalNetInterfaces := netInterfaces