🤖 fix: persist status URL using storage.ts pattern (#832)

Status URLs now use the standard storage.ts key pattern and are properly
migrated on workspace rename.

## Changes
- Add `getStatusUrlKey` to storage.ts with standard format
(`statusUrl:{workspaceId}`)
- Register in `PERSISTENT_WORKSPACE_KEY_FUNCTIONS` for fork/delete
- Add `migrateWorkspaceStorage` for rename support (fixes pre-existing
bug where all workspace storage was lost on rename)
- Update `StreamingMessageAggregator` to use centralized key function

## Why
Previously, status URLs used a non-standard key format
(`mux:workspace:...`) that wasn't registered in storage.ts, so:
1. Keys weren't copied on fork
2. Keys weren't deleted on workspace removal  
3. Keys weren't migrated on rename (pre-existing bug affecting all
workspace storage)

_Generated with `mux`_

Author: ammar-agent

src/browser/contexts/WorkspaceContext.tsx

@@ -11,7 +11,7 @@ import {
 import type { FrontendWorkspaceMetadata } from "@/common/types/workspace";
 import type { WorkspaceSelection } from "@/browser/components/ProjectSidebar";
 import type { RuntimeConfig } from "@/common/types/runtime";
-import { deleteWorkspaceStorage } from "@/common/constants/storage";
+import { deleteWorkspaceStorage, migrateWorkspaceStorage } from "@/common/constants/storage";
 import { usePersistedState } from "@/browser/hooks/usePersistedState";
 import { useProjectContext } from "@/browser/contexts/ProjectContext";
 import { useWorkspaceStoreRaw } from "@/browser/stores/WorkspaceStore";
@@ -320,6 +320,11 @@ export function WorkspaceProvider(props: WorkspaceProviderProps) {
       try {
         const result = await window.api.workspace.rename(workspaceId, newName);
         if (result.success) {
+          const newWorkspaceId = result.data.newWorkspaceId;
+
+          // Migrate localStorage keys from old to new workspace ID
+          migrateWorkspaceStorage(workspaceId, newWorkspaceId);
+
           // Backend has already updated the config - reload projects to get updated state
           await refreshProjects();
 
@@ -328,8 +333,6 @@ export function WorkspaceProvider(props: WorkspaceProviderProps) {
 
           // Update selected workspace if it was renamed
           if (selectedWorkspace?.workspaceId === workspaceId) {
-            const newWorkspaceId = result.data.newWorkspaceId;
-
             // Get updated workspace metadata from backend
             const newMetadata = await window.api.workspace.getInfo(newWorkspaceId);
             if (newMetadata) {

src/browser/utils/messages/StreamingMessageAggregator.ts

@@ -31,6 +31,7 @@ import type {
 import { isDynamicToolPart } from "@/common/types/toolParts";
 import { createDeltaStorage, type DeltaRecordStorage } from "./StreamingTPSCalculator";
 import { computeRecencyTimestamp } from "./recency";
+import { getStatusUrlKey } from "@/common/constants/storage";
 
 // Maximum number of messages to display in the DOM for performance
 // Full history is still maintained internally for token counting and stats
@@ -125,18 +126,11 @@ export class StreamingMessageAggregator {
     this.updateRecency();
   }
 
-  /** localStorage key for persisting lastStatusUrl. Only call when workspaceId is defined. */
-  private getStatusUrlKey(): string | undefined {
-    if (!this.workspaceId) return undefined;
-    return `mux:workspace:${this.workspaceId}:lastStatusUrl`;
-  }
-
   /** Load lastStatusUrl from localStorage */
   private loadLastStatusUrl(): string | undefined {
-    const key = this.getStatusUrlKey();
-    if (!key) return undefined;
+    if (!this.workspaceId) return undefined;
     try {
-      const stored = localStorage.getItem(key);
+      const stored = localStorage.getItem(getStatusUrlKey(this.workspaceId));
       return stored ?? undefined;
     } catch {
       return undefined;
@@ -148,10 +142,9 @@ export class StreamingMessageAggregator {
    * Once set, the URL can only be replaced with a new URL, never deleted.
    */
   private saveLastStatusUrl(url: string): void {
-    const key = this.getStatusUrlKey();
-    if (!key) return;
+    if (!this.workspaceId) return;
     try {
-      localStorage.setItem(key, url);
+      localStorage.setItem(getStatusUrlKey(this.workspaceId), url);
     } catch {
       // Ignore localStorage errors
     }

src/common/constants/storage.ts

@@ -162,6 +162,15 @@ export function getFileTreeExpandStateKey(workspaceId: string): string {
   return `fileTreeExpandState:${workspaceId}`;
 }
 
+/**
+ * Get the localStorage key for persisted status URL for a workspace
+ * Stores the last URL set via status_set tool (survives compaction)
+ * Format: "statusUrl:{workspaceId}"
+ */
+export function getStatusUrlKey(workspaceId: string): string {
+  return `statusUrl:${workspaceId}`;
+}
+
 /**
  * Get the localStorage key for unified Review search state per workspace
  * Stores: { input: string, useRegex: boolean, matchCase: boolean }
@@ -202,6 +211,7 @@ const PERSISTENT_WORKSPACE_KEY_FUNCTIONS: Array<(workspaceId: string) => string>
   getFileTreeExpandStateKey,
   getReviewSearchStateKey,
   getAutoCompactionEnabledKey,
+  getStatusUrlKey,
   // Note: getAutoCompactionThresholdKey is per-model, not per-workspace
 ];
 
@@ -242,3 +252,12 @@ export function deleteWorkspaceStorage(workspaceId: string): void {
     localStorage.removeItem(key);
   }
 }
+
+/**
+ * Migrate all workspace-specific localStorage keys from old to new workspace ID
+ * Should be called when a workspace is renamed to preserve settings
+ */
+export function migrateWorkspaceStorage(oldWorkspaceId: string, newWorkspaceId: string): void {
+  copyWorkspaceStorage(oldWorkspaceId, newWorkspaceId);
+  deleteWorkspaceStorage(oldWorkspaceId);
+}