address review: scroll only when needed and smoothly, tighten the visual search needle

scrollIntoView re-centered every element unconditionally and instantly, which is the page jump between the daily set and explore on bing. The pointer move now scrolls only when the element is actually outside the viewport, smoothly, and polls the rect until the async scroll settles before computing the path.

Visual search matches the full 'visual search streak' label. Plain 'visual search' can also hit a dashboard element that goes stale mid-interaction, and the guessed 'image search' needle is gone.

src/mouse_trajectory.py

@@ -314,12 +314,41 @@ class MouseUtils:
 	def move_to_element(self, element: WebElement, visualize: bool=True):
 		# The pointer is moved to viewport coordinates, so an element below the
 		# fold yields a target outside the window and the driver rejects the move
-		# with MoveTargetOutOfBoundsException. Bring it into view first.
-		self.driver.execute_script(
-			"arguments[0].scrollIntoView({block: 'center', inline: 'center'});",
-			element
-		)
-		time.sleep(0.4)
+		# with MoveTargetOutOfBoundsException. Bring it into view first, but only
+		# when it actually is out of view: unconditionally re-centering visible
+		# elements is what caused the page to jump between tasks. When scrolling
+		# is needed it is smooth, and since smooth scrolling is asynchronous, the
+		# rect is polled until it stops moving before the path is computed.
+		fully_in_view = self.driver.execute_script("""
+			var r = arguments[0].getBoundingClientRect();
+			return (
+				r.top >= 0 && r.left >= 0 &&
+				r.bottom <= (window.innerHeight || document.documentElement.clientHeight) &&
+				r.right <= (window.innerWidth || document.documentElement.clientWidth)
+			);
+		""", element)
+
+		if not fully_in_view:
+			self.driver.execute_script(
+				"arguments[0].scrollIntoView({block: 'center', inline: 'center', behavior: 'smooth'});",
+				element
+			)
+
+			last_rect = None
+
+			for _ in range(20):
+				time.sleep(0.15)
+
+				rect = self.driver.execute_script(
+					"var r = arguments[0].getBoundingClientRect();"
+					"return [Math.round(r.top), Math.round(r.left)];",
+					element
+				)
+
+				if rect == last_rect:
+					break
+
+				last_rect = rect
 
 		current_mouse_position = self.get_current_mouse_position()