Add task reports and streamline GPU charts

audit/internal/webui/metricsdb.go

@@ -22,6 +22,13 @@ type MetricsDB struct {
 	db *sql.DB
 }
 
+func (m *MetricsDB) Close() error {
+	if m == nil || m.db == nil {
+		return nil
+	}
+	return m.db.Close()
+}
+
 // openMetricsDB opens (or creates) the metrics database at the given path.
 func openMetricsDB(path string) (*MetricsDB, error) {
 	if err := os.MkdirAll(filepath.Dir(path), 0755); err != nil {
@@ -164,6 +171,23 @@ func (m *MetricsDB) LoadAll() ([]platform.LiveMetricSample, error) {
 	return m.loadSamples(`SELECT ts,cpu_load_pct,mem_load_pct,power_w FROM sys_metrics ORDER BY ts`, nil)
 }
 
+// LoadBetween returns samples in chronological order within the given time window.
+func (m *MetricsDB) LoadBetween(start, end time.Time) ([]platform.LiveMetricSample, error) {
+	if m == nil {
+		return nil, nil
+	}
+	if start.IsZero() || end.IsZero() {
+		return nil, nil
+	}
+	if end.Before(start) {
+		start, end = end, start
+	}
+	return m.loadSamples(
+		`SELECT ts,cpu_load_pct,mem_load_pct,power_w FROM sys_metrics WHERE ts>=? AND ts<=? ORDER BY ts`,
+		start.Unix(), end.Unix(),
+	)
+}
+
 // loadSamples reconstructs LiveMetricSample rows from the normalized tables.
 func (m *MetricsDB) loadSamples(query string, args ...any) ([]platform.LiveMetricSample, error) {
 	rows, err := m.db.Query(query, args...)
@@ -364,9 +388,6 @@ func (m *MetricsDB) ExportCSV(w io.Writer) error {
 	return cw.Error()
 }
 
-// Close closes the database.
-func (m *MetricsDB) Close() { _ = m.db.Close() }
-
 func nullFloat(v float64) sql.NullFloat64 {
 	return sql.NullFloat64{Float64: v, Valid: true}
 }