feat(workers): Add dual-transport preflight system

Workers now run both curl and http (Puppeteer) preflights on startup:
- curl-preflight.ts: Tests axios + proxy via httpbin.org
- puppeteer-preflight.ts: Tests browser + StealthPlugin via fingerprint.com
  (with amiunique.org fallback)
- Migration 084: Adds preflight columns to worker_registry and method
  column to worker_tasks
- Workers report preflight status, IP, fingerprint, and response time
- Tasks can require specific transport method (curl/http)
- Dashboard shows Transport column with preflight status badges

🤖 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

@@ -51,6 +51,7 @@ export interface WorkerTask {
   platform: string | null;
   status: TaskStatus;
   priority: number;
+  method: 'curl' | 'http' | null;  // Transport method: curl=axios/proxy, http=Puppeteer/browser
   scheduled_for: Date | null;
   worker_id: string | null;
   claimed_at: Date | null;
@@ -152,23 +153,33 @@ class TaskService {
    * Claim a task atomically for a worker
    * If role is null, claims ANY available task (role-agnostic worker)
    * Returns null if task pool is paused.
+   *
+   * @param role - Task role to claim, or null for any task
+   * @param workerId - Worker ID claiming the task
+   * @param curlPassed - Whether worker passed curl preflight (default true for backward compat)
+   * @param httpPassed - Whether worker passed http/Puppeteer preflight (default false)
    */
-  async claimTask(role: TaskRole | null, workerId: string): Promise<WorkerTask | null> {
+  async claimTask(
+    role: TaskRole | null,
+    workerId: string,
+    curlPassed: boolean = true,
+    httpPassed: boolean = false
+  ): Promise<WorkerTask | null> {
     // Check if task pool is paused - don't claim any tasks
     if (isTaskPoolPaused()) {
       return null;
     }
 
     if (role) {
-      // Role-specific claiming - use the SQL function
+      // Role-specific claiming - use the SQL function with preflight capabilities
       const result = await pool.query(
-        `SELECT * FROM claim_task($1, $2)`,
-        [role, workerId]
+        `SELECT * FROM claim_task($1, $2, $3, $4)`,
+        [role, workerId, curlPassed, httpPassed]
       );
       return (result.rows[0] as WorkerTask) || null;
     }
 
-    // Role-agnostic claiming - claim ANY pending task
+    // Role-agnostic claiming - claim ANY pending task matching worker capabilities
     const result = await pool.query(`
       UPDATE worker_tasks
       SET
@@ -179,6 +190,12 @@ class TaskService {
         SELECT id FROM worker_tasks
         WHERE status = 'pending'
           AND (scheduled_for IS NULL OR scheduled_for <= NOW())
+          -- Method compatibility: worker must have passed the required preflight
+          AND (
+            method IS NULL  -- No preference, any worker can claim
+            OR (method = 'curl' AND $2 = TRUE)
+            OR (method = 'http' AND $3 = TRUE)
+          )
           -- Exclude stores that already have an active task
           AND (dispensary_id IS NULL OR dispensary_id NOT IN (
             SELECT dispensary_id FROM worker_tasks
@@ -190,7 +207,7 @@ class TaskService {
         FOR UPDATE SKIP LOCKED
       )
       RETURNING *
-    `, [workerId]);
+    `, [workerId, curlPassed, httpPassed]);
 
     return (result.rows[0] as WorkerTask) || null;
   }