feat: add filter toggle dashboard card (frontend)

**New Components:**
- FiltersConfigCard — Card with toggle switches for all 11 entry filters
- Switch UI component (shadcn/ui with Radix)
- useFilterConfig hook — Fetch & update filters via API
- FilterConfig types

**Features:**
- Live toggle switches for 11 filters (flash_crash, regime, risk, session, signal_combination, h1_bias, time_filter, cooldown, etc.)
- Real-time updates — no page refresh needed
- Shows enabled/disabled count badge
- Filter descriptions + last updated timestamp
- Auto-refresh every 30 seconds
- Refresh button with loading state
- Error handling + retry

**Integration:**
- Added @radix-ui/react-switch dependency
- Added Row 5 to dashboard (grid-cols-2)
- FiltersConfigCard takes left half of new row

**Usage:**
User can toggle any filter ON/OFF from dashboard → API updates filter_config.json → Bot reloads config next loop (live update, no restart)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

web-dashboard/package.json

@@ -10,6 +10,7 @@
   },
   "dependencies": {
     "@radix-ui/react-collapsible": "^1.1.12",
+    "@radix-ui/react-switch": "^1.1.2",
     "@radix-ui/react-tabs": "^1.1.13",
     "@radix-ui/react-tooltip": "^1.2.8",
     "class-variance-authority": "^0.7.1",