fix: Build args format for version info + schema-tolerant routes

CI/CD:
- Fix build_args format in woodpecker CI (comma-separated, not YAML list)
- This fixes "unknown" SHA/version showing on remote deployments

Backend schema-tolerant fixes (graceful fallbacks when tables missing):
- users.ts: Check which columns exist before querying
- worker-registry.ts: Return empty result if table doesn't exist
- task-service.ts: Add tableExists() helper, handle missing tables/views
- proxies.ts: Return totalProxies in test-all response

Frontend fixes:
- Proxies: Use total from response for accurate progress display
- SEO PagesTab: Dim Generate button when no AI provider active

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

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

backend/src/tasks/task-service.ts

@@ -10,6 +10,17 @@
 
 import { pool } from '../db/pool';
 
+// Helper to check if a table exists
+async function tableExists(tableName: string): Promise<boolean> {
+  const result = await pool.query(`
+    SELECT EXISTS (
+      SELECT FROM information_schema.tables
+      WHERE table_name = $1
+    ) as exists
+  `, [tableName]);
+  return result.rows[0].exists;
+}
+
 export type TaskRole =
   | 'store_discovery'
   | 'entry_point_discovery'
@@ -270,6 +281,11 @@ class TaskService {
    * List tasks with filters
    */
   async listTasks(filter: TaskFilter = {}): Promise<WorkerTask[]> {
+    // Return empty list if table doesn't exist
+    if (!await tableExists('worker_tasks')) {
+      return [];
+    }
+
     const conditions: string[] = [];
     const params: (string | number | string[])[] = [];
     let paramIndex = 1;
@@ -323,21 +339,41 @@ class TaskService {
    * Get capacity metrics for all roles
    */
   async getCapacityMetrics(): Promise<CapacityMetrics[]> {
-    const result = await pool.query(
-      `SELECT * FROM v_worker_capacity`
-    );
-    return result.rows as CapacityMetrics[];
+    // Return empty metrics if worker_tasks table doesn't exist
+    if (!await tableExists('worker_tasks')) {
+      return [];
+    }
+
+    try {
+      const result = await pool.query(
+        `SELECT * FROM v_worker_capacity`
+      );
+      return result.rows as CapacityMetrics[];
+    } catch {
+      // View may not exist
+      return [];
+    }
   }
 
   /**
    * Get capacity metrics for a specific role
    */
   async getRoleCapacity(role: TaskRole): Promise<CapacityMetrics | null> {
-    const result = await pool.query(
-      `SELECT * FROM v_worker_capacity WHERE role = $1`,
-      [role]
-    );
-    return (result.rows[0] as CapacityMetrics) || null;
+    // Return null if worker_tasks table doesn't exist
+    if (!await tableExists('worker_tasks')) {
+      return null;
+    }
+
+    try {
+      const result = await pool.query(
+        `SELECT * FROM v_worker_capacity WHERE role = $1`,
+        [role]
+      );
+      return (result.rows[0] as CapacityMetrics) || null;
+    } catch {
+      // View may not exist
+      return null;
+    }
   }
 
   /**
@@ -463,12 +499,6 @@ class TaskService {
    * Get task counts by status for dashboard
    */
   async getTaskCounts(): Promise<Record<TaskStatus, number>> {
-    const result = await pool.query(
-      `SELECT status, COUNT(*) as count
-       FROM worker_tasks
-       GROUP BY status`
-    );
-
     const counts: Record<TaskStatus, number> = {
       pending: 0,
       claimed: 0,
@@ -478,6 +508,17 @@ class TaskService {
       stale: 0,
     };
 
+    // Return empty counts if table doesn't exist
+    if (!await tableExists('worker_tasks')) {
+      return counts;
+    }
+
+    const result = await pool.query(
+      `SELECT status, COUNT(*) as count
+       FROM worker_tasks
+       GROUP BY status`
+    );
+
     for (const row of result.rows) {
       const typedRow = row as { status: TaskStatus; count: string };
       counts[typedRow.status] = parseInt(typedRow.count, 10);