feat: add supervisor workspace and traceable story graph

Extend the existing heartbeat workspace with scoped work reviews, result-specific story graphs, source inspection, and pinned conversation or task feedback. Connect confirmed continuation and local knowledge entity previews through the desktop APIs, and preserve result history and user corrections in schema 43.

Include focused regression tests, an isolated visual fixture, and implementation evidence. Full event-by-event replay, Experiment targets, no-change handling, and cancellation remain incomplete; this commit does not claim complete feature acceptance. Existing automatic plans remain active when the application entry is disabled.

Release note: Review work progress in the Supervisor workspace, trace graph events to saved sources, and open a matching review from pinned conversation or task feedback.

src/shared/workbar-contracts.ts

@@ -183,6 +183,7 @@ export type WorkbarExecutionTargetRef = z.infer<
 
 export const workbarTargetRefSchema = z.union([
   workbarExecutionTargetRefSchema,
+  z.object({ type: z.literal('task'), taskId: z.string().min(1).max(128) }).strict(),
   z
     .object({
       type: z.literal('conversation'),
@@ -206,7 +207,7 @@ export const workbarTabInstanceSchema = z
   .superRefine((instance, context) => {
     if (
       instance.appId === 'terminal' &&
-      (!instance.targetRef || instance.targetRef.type === 'conversation')
+      (!instance.targetRef || !['local', 'project'].includes(instance.targetRef.type))
     ) {
       context.addIssue({
         code: 'custom',
@@ -227,14 +228,18 @@ export const workbarTabInstanceSchema = z
     }
     if (
       instance.appId !== 'browser' &&
+      instance.appId !== 'tasks' &&
       instance.targetRef?.type === 'conversation'
     ) {
       context.addIssue({
         code: 'custom',
         path: ['targetRef'],
-        message: 'Conversation bindings are reserved for browser instances'
+        message: 'Conversation bindings require browser or tasks instances'
       })
     }
+    if (instance.targetRef?.type === 'task' && instance.appId !== 'tasks') {
+      context.addIssue({ code: 'custom', path: ['targetRef'], message: 'Task bindings require tasks instances' })
+    }
   })
 export type WorkbarTabInstance = z.infer<
   typeof workbarTabInstanceSchema