Wave 3: SSE structured logs, crash analyzer, session fingerprint

- Task #3: Update SSE stream to emit structured log events
  (type: "log" for entries, type: "metrics" every 5s, ?format=legacy for backward compat)
- Task #10: Create crash pattern analyzer module
  (6 patterns: memory_exhaustion, dom_bloat, rate_limited, consent_loop, scroll_timeout, element_stale)
  (confidence scoring, auto-fix params, summarize_crash_patterns for recurring issues)
- Task #13: Capture session fingerprint in backend
  (user_agent, platform, timezone, webgl, canvas, bot_detection_tests)
  (saved on success and failure for debugging)

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

modules/database.py

@@ -430,6 +430,47 @@ class DatabaseManager:
 
             log.debug(f"Incremental save: {len(reviews)} reviews for job {job_id}")
 
+    async def update_session_fingerprint(
+        self,
+        job_id: UUID,
+        session_fingerprint: Dict[str, Any]
+    ):
+        """
+        Update the session fingerprint for a job.
+
+        This should be called early in the scraping process after the browser
+        fingerprint is captured, to record browser characteristics for
+        bot detection analysis.
+
+        Args:
+            job_id: Job UUID
+            session_fingerprint: Dictionary containing browser fingerprint data:
+                - user_agent: Browser user agent string
+                - platform: OS platform
+                - language: Primary language
+                - languages: List of accepted languages
+                - timezone: Timezone string
+                - screen: {width, height, colorDepth}
+                - viewport: {width, height}
+                - webgl_vendor: WebGL vendor string
+                - webgl_renderer: WebGL renderer string
+                - canvas_fingerprint: Canvas fingerprint hash
+                - hardware_concurrency: Number of CPU cores
+                - device_memory: Device memory in GB
+                - bot_detection_tests: {webdriver_hidden, chrome_runtime, permissions_query}
+                - captured_at: ISO timestamp when fingerprint was captured
+        """
+        async with self.pool.acquire() as conn:
+            await conn.execute("""
+                UPDATE jobs
+                SET
+                    session_fingerprint = $2::jsonb,
+                    updated_at = NOW()
+                WHERE job_id = $1
+            """, job_id, json.dumps(session_fingerprint))
+
+            log.debug(f"Updated session fingerprint for job {job_id}")
+
     async def mark_job_partial(
         self,
         job_id: UUID,