Add auto-advance: click Next, scroll to top, capture next page

After each capture the controller asks the vision model to locate a 'Next'
control (returned as normalized screen coordinates), clicks it via OS input,
scrolls to top, and continues the loop. Configurable via SCREEN_LEADS_AUTO_NEXT
/ _NEXT_LOAD_PAUSE / _MAX_AUTO_NEXT, with a per-run safety cap.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

ai/extractor.py

@@ -88,3 +88,39 @@ def classify_page(screenshot_path: str) -> dict[str, Any]:
         output_config={"format": {"type": "json_schema", "schema": _CLASSIFY_SCHEMA}},
     )
     return _first_json(response)
+
+
+_NEXT_SCHEMA = {
+    "type": "object",
+    "properties": {
+        "found": {"type": "boolean"},
+        "x": {"type": "number"},      # 0..1 fraction of image width  (button centre)
+        "y": {"type": "number"},      # 0..1 fraction of image height
+        "label": {"type": "string"},
+    },
+    "required": ["found", "x", "y", "label"],
+    "additionalProperties": False,
+}
+
+_NEXT_PROMPT = (
+    "Look at this screenshot for a control that advances to the NEXT item or page — "
+    "for example a button or link labelled 'Next', 'Next result', 'See next profile', "
+    "or a right-facing pagination arrow ('>' / '›' / '→'). Ignore 'Back'/'Previous' "
+    "and unrelated arrows. If such a control is clearly visible, set found=true and give "
+    "its CENTRE position as fractions of the image: x = left→right (0.0–1.0), "
+    "y = top→bottom (0.0–1.0), plus its visible label. If none is visible, "
+    "return found=false, x=0, y=0, label=\"\"."
+)
+
+
+def find_next_button(screenshot_path: str) -> dict[str, Any]:
+    response = _client().messages.create(
+        model=ANTHROPIC_MODEL,
+        max_tokens=256,
+        messages=[{
+            "role": "user",
+            "content": [_image_block(screenshot_path), {"type": "text", "text": _NEXT_PROMPT}],
+        }],
+        output_config={"format": {"type": "json_schema", "schema": _NEXT_SCHEMA}},
+    )
+    return _first_json(response)