fix: count only live dashboard sessions

internal/store/postgres/stats.go

@@ -6,9 +6,10 @@ import (
 )
 
 type FrameworkStats struct {
-	Runs   int `json:"runs"`
-	Tools  int `json:"tools"`
-	Errors int `json:"errors"`
+	ActiveSessions int `json:"active_sessions"`
+	Runs           int `json:"runs"`
+	Tools          int `json:"tools"`
+	Errors         int `json:"errors"`
 }
 
 type Summary struct {
@@ -44,23 +45,47 @@ func (d *DB) GetSummary(ctx context.Context) (*Summary, error) {
 	now := time.Now()
 	midnight := time.Date(now.Year(), now.Month(), now.Day(), 0, 0, 0, 0, now.Location())
 
-	// Active sessions: sessions with a session.start but no session.end (last 7 days)
+	// Active sessions are open sessions with recent activity. Some hook sources can
+	// miss session.end, so "started but never ended" alone overstates live work.
 	activeQ := `
-		SELECT COUNT(DISTINCT e.session_id)
-		FROM events e
-		WHERE e.type = 'session.start'
-		  AND e.session_id IS NOT NULL
-		  AND e.ts >= $1
-		  AND NOT EXISTS (
-		      SELECT 1
-		      FROM events e2
-		      WHERE e2.type = 'session.end'
-		        AND e2.session_id = e.session_id
-		  )
+		WITH session_groups AS (
+			SELECT
+				session_id,
+				COALESCE(MAX(source_framework), 'unknown') AS framework,
+				MAX(ts) AS last_event_at,
+				BOOL_OR(type = 'session.start') AS has_start,
+				BOOL_OR(type = 'session.end') AS has_end
+			FROM events
+			WHERE session_id IS NOT NULL
+			GROUP BY session_id
+		)
+		SELECT framework, COUNT(*)
+		FROM session_groups
+		WHERE has_start
+		  AND NOT has_end
+		  AND last_event_at >= $1
+		GROUP BY framework
 	`
+	activeRows, err := d.sql.QueryContext(ctx, activeQ, now.Add(-15*time.Minute))
+	if err != nil {
+		return nil, err
+	}
+	defer activeRows.Close()
+
+	byFramework := make(map[string]FrameworkStats)
 	var activeSessions int
-	activeSessionsSince := time.Now().Add(-7 * 24 * time.Hour)
-	if err := d.sql.QueryRowContext(ctx, activeQ, activeSessionsSince).Scan(&activeSessions); err != nil {
+	for activeRows.Next() {
+		var fw string
+		var count int
+		if err := activeRows.Scan(&fw, &count); err != nil {
+			return nil, err
+		}
+		fs := byFramework[fw]
+		fs.ActiveSessions = count
+		byFramework[fw] = fs
+		activeSessions += count
+	}
+	if err := activeRows.Err(); err != nil {
 		return nil, err
 	}
 
@@ -83,7 +108,6 @@ func (d *DB) GetSummary(ctx context.Context) (*Summary, error) {
 	}
 	defer rows.Close()
 
-	byFramework := make(map[string]FrameworkStats)
 	var totalRuns, totalTools, totalErrors int
 
 	for rows.Next() {
@@ -92,6 +116,9 @@ func (d *DB) GetSummary(ctx context.Context) (*Summary, error) {
 		if err := rows.Scan(&fw, &fs.Runs, &fs.Tools, &fs.Errors); err != nil {
 			return nil, err
 		}
+		if existing, ok := byFramework[fw]; ok {
+			fs.ActiveSessions = existing.ActiveSessions
+		}
 		byFramework[fw] = fs
 		totalRuns += fs.Runs
 		totalTools += fs.Tools