fix: refine floating workspace controls

Keep ScaleInfo pinned to the map corner and move the centered timeline above collisions, preventing the previous conditional offset from lifting the scale. Remove collapsed Agent rail width reservation and add timeline state transitions.

src/features/workbench/workspace/workbench-main-frame.tsx

@@ -1,4 +1,5 @@
 import { ArrowLeft, FileChartColumnIncreasing } from "lucide-react";
+import { AnimatePresence, motion, useReducedMotion } from "motion/react";
 import type { ReactNode } from "react";
 import { cn } from "@/shared/ui/cn";
 import { OPERATIONAL_TIMELINE_LAYOUT } from "../operational-timeline/operational-timeline-model";
@@ -15,7 +16,7 @@ type WorkbenchMainFrameProps = {
   mapOverlay?: ReactNode;
   timelineContent: ReactNode;
   timelineMode: "compact" | "expanded" | "summary";
-  reserveMapScaleSpace: boolean;
+  timelineBottom: number;
   activeArtifact: AnalysisArtifact | null;
   pendingArtifact: AnalysisArtifact | null;
   surfaceMode: WorkbenchSurfaceMode;
@@ -32,7 +33,7 @@ export function WorkbenchMainFrame({
   mapOverlay,
   timelineContent,
   timelineMode,
-  reserveMapScaleSpace,
+  timelineBottom,
   activeArtifact,
   pendingArtifact,
   surfaceMode,
@@ -43,8 +44,12 @@ export function WorkbenchMainFrame({
   onCollapseArtifact,
   onDestroyArtifact
 }: WorkbenchMainFrameProps) {
+  const prefersReducedMotion = useReducedMotion();
   const showMap = surfaceMode !== "focus";
   const showArtifact = activeArtifact && surfaceMode !== "map_only";
+  const timelineTransition = prefersReducedMotion
+    ? { duration: 0 }
+    : { duration: 0.28, ease: [0.22, 1, 0.36, 1] as const };
 
   return (
     <div
@@ -113,18 +118,30 @@ export function WorkbenchMainFrame({
         ) : null}
       </div>
 
-      <div
-        className="pointer-events-auto absolute bottom-3 left-3 z-40 mx-auto min-h-0"
-        style={{
+      <motion.div
+        className="pointer-events-auto absolute left-3 z-40 mx-auto min-h-0"
+        initial={false}
+        animate={{
+          bottom: timelineBottom,
           maxWidth: OPERATIONAL_TIMELINE_LAYOUT[timelineMode].maxWidth,
-          right: reserveMapScaleSpace
-            ? OPERATIONAL_TIMELINE_LAYOUT.mapScaleSafeWidth +
-              OPERATIONAL_TIMELINE_LAYOUT.floatingGap
-            : 12
+          right: 12
         }}
+        transition={timelineTransition}
       >
-        {timelineContent}
-      </div>
+        <AnimatePresence initial={false}>
+          {timelineContent ? (
+            <motion.div
+              key="operational-timeline"
+              initial={prefersReducedMotion ? false : { opacity: 0, y: 14, scale: 0.985 }}
+              animate={{ opacity: 1, y: 0, scale: 1 }}
+              exit={prefersReducedMotion ? { opacity: 0 } : { opacity: 0, y: 12, scale: 0.985 }}
+              transition={timelineTransition}
+            >
+              {timelineContent}
+            </motion.div>
+          ) : null}
+        </AnimatePresence>
+      </motion.div>
     </div>
   );
 }