fix(dashboard): fix chart crash, field name mismatches, and demo data injection

- overview.js: fix time-series chart crash (data is {series:[...]}, not array; field is 'time' not 'hour')
- monitoring.js: use fallback field names (total_tokens/tokens, duration_ms/duration) for WebSocket vs API compat
- monitoring.js: disable localhost demo data injection that mixed fake data with real
- websocket.js: fix duplicate condition and field name mismatches in dead-code handlers
- logging/mod.rs: add info! logs for successful DB insert and broadcast count for diagnostics

static/js/pages/overview.js

@@ -129,13 +129,14 @@ class OverviewPage {
     async loadRequestsChart() {
         try {
             const data = await window.api.get('/usage/time-series');
+            const series = data.series || [];
             
             const chartData = {
-                labels: data.map(item => item.hour),
+                labels: series.map(item => item.time),
                 datasets: [
                     {
                         label: 'Requests',
-                        data: data.map(item => item.requests),
+                        data: series.map(item => item.requests),
                         color: '#3b82f6',
                         fill: true
                     }