feat: Stealth worker system with mandatory proxy rotation

## Worker System
- Role-agnostic workers that can handle any task type
- Pod-based architecture with StatefulSet (5-15 pods, 5 workers each)
- Custom pod names (Aethelgard, Xylos, Kryll, etc.)
- Worker registry with friendly names and resource monitoring
- Hub-and-spoke visualization on JobQueue page

## Stealth & Anti-Detection (REQUIRED)
- Proxies are MANDATORY - workers fail to start without active proxies
- CrawlRotator initializes on worker startup
- Loads proxies from `proxies` table
- Auto-rotates proxy + fingerprint on 403 errors
- 12 browser fingerprints (Chrome, Firefox, Safari, Edge)
- Locale/timezone matching for geographic consistency

## Task System
- Renamed product_resync → product_refresh
- Task chaining: store_discovery → entry_point → product_discovery
- Priority-based claiming with FOR UPDATE SKIP LOCKED
- Heartbeat and stale task recovery

## UI Updates
- JobQueue: Pod visualization, resource monitoring on hover
- WorkersDashboard: Simplified worker list
- Removed unused filters from task list

## Other
- IP2Location service for visitor analytics
- Findagram consumer features scaffolding
- Documentation updates

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/src/services/crawl-rotator.ts

@@ -109,14 +109,14 @@ export class ProxyRotator {
           username,
           password,
           protocol,
-          is_active as "isActive",
-          last_used_at as "lastUsedAt",
+          active as "isActive",
+          last_tested_at as "lastUsedAt",
           failure_count as "failureCount",
-          success_count as "successCount",
-          avg_response_time_ms as "avgResponseTimeMs"
+          0 as "successCount",
+          response_time_ms as "avgResponseTimeMs"
         FROM proxies
-        WHERE is_active = true
-        ORDER BY failure_count ASC, last_used_at ASC NULLS FIRST
+        WHERE active = true
+        ORDER BY failure_count ASC, last_tested_at ASC NULLS FIRST
       `);
 
       this.proxies = result.rows;
@@ -192,11 +192,11 @@ export class ProxyRotator {
           UPDATE proxies
           SET
             failure_count = failure_count + 1,
-            last_failure_at = NOW(),
-            last_error = $2,
-            is_active = CASE WHEN failure_count >= 4 THEN false ELSE is_active END
+            updated_at = NOW(),
+            test_result = $2,
+            active = CASE WHEN failure_count >= 4 THEN false ELSE active END
           WHERE id = $1
-        `, [proxyId, error || null]);
+        `, [proxyId, error || 'failed']);
       } catch (err) {
         console.error(`[ProxyRotator] Failed to update proxy ${proxyId}:`, err);
       }
@@ -226,12 +226,13 @@ export class ProxyRotator {
         await this.pool.query(`
           UPDATE proxies
           SET
-            success_count = success_count + 1,
-            last_used_at = NOW(),
-            avg_response_time_ms = CASE
-              WHEN avg_response_time_ms IS NULL THEN $2
-              ELSE (avg_response_time_ms * 0.8) + ($2 * 0.2)
-            END
+            last_tested_at = NOW(),
+            test_result = 'success',
+            response_time_ms = CASE
+              WHEN response_time_ms IS NULL THEN $2
+              ELSE (response_time_ms * 0.8 + $2 * 0.2)::integer
+            END,
+            updated_at = NOW()
           WHERE id = $1
         `, [proxyId, responseTimeMs || null]);
       } catch (err) {