refactor: stop persisting workspace state in the browser

frontend/src/workspaces/preferences.ts

@@ -5,36 +5,31 @@ export interface WorkspacePreference {
   thinking?: string;
 }
 
-const STORAGE_KEY = "thothii.workspace-registry.v1.preferences";
+let current: WorkspacePreference | undefined;
 
-function storage(): Storage | undefined {
-  try { return window.localStorage; } catch { return undefined; }
+function snapshot(value: WorkspacePreference | undefined): WorkspacePreference {
+  return value === undefined ? {} : { ...value };
 }
 
-function parse(raw: string | null): WorkspacePreference | undefined {
-  if (raw === null) return undefined;
-  try {
-    const value = JSON.parse(raw);
-    return value && typeof value === "object" && !Array.isArray(value) ? value as WorkspacePreference : undefined;
-  } catch {
-    return undefined;
-  }
-}
-
-/** Anonymous, non-secret browser choices for the workspace session composer. */
+/** Ephemeral workspace choices for the current application process. */
 export const workspacePreferences = {
   load(): WorkspacePreference {
-    return parse(storage()?.getItem(STORAGE_KEY) ?? null) ?? {};
+    return snapshot(current);
   },
 
   save(value: WorkspacePreference): WorkspacePreference {
-    try { storage()?.setItem(STORAGE_KEY, JSON.stringify(value)); } catch { /* storage is optional */ }
-    return value;
+    current = { ...value };
+    return snapshot(current);
   },
 
-  /** Copy the pre-local-storage server values only when this browser has no saved choice. */
-  migrate(legacy: WorkspacePreference): WorkspacePreference {
-    const current = storage()?.getItem(STORAGE_KEY);
-    return current === null || current === undefined ? this.save(legacy) : this.load();
+  /** Seed current memory from backend installation settings only before the first local choice. */
+  migrate(settings: WorkspacePreference): WorkspacePreference {
+    if (current === undefined) current = { ...settings };
+    return snapshot(current);
+  },
+
+  /** Clear ephemeral state on application/test lifecycle reset. */
+  reset(): void {
+    current = undefined;
   },
 };