feat: let agents read supervisor story graphs

Expose saved decisions, timelines and source evidence through read-only Story Graph tools across Model, Harness and local/remote OpenCode and Continue. Supervisor enablement and runtime assignments govern discovery and calls; reads do not invoke models or modify stored evidence. Remote use requires matching Desktop and Agent changes.

Make Continue discussion show the complete editable message with a separated destination and shared action layout. Sending uses the visible draft without reattaching removed context.

Validation: existing focused MCP, runtime, controlled Linux Host, discussion component and Electron layout checks plus typechecks; staged diff check passed. Cross-scope fact reuse, historical reconstruction and full package acceptance remain deferred.

Release note: Agents can consult saved supervisor decisions and their sources when continuing work. Continue discussion now lets you review and edit the complete message before sending.

src/main/assistant/supervision-production.test.ts

@@ -86,6 +86,12 @@ it('persists publication failure and resumes with saved navigation without model
     expect(batch.output.summary).toBe(summary)
     expect(batch.output.events[0]!.description).toBe(description)
   }
+  const calls = f.respond.mock.calls.length
+  expect(f.db.readStoryGraph('story_graph_search', { query: 'Retained source qualification', scope: { kind: 'global' }, object_types: ['event'] }))
+    .toMatchObject({ page: { total_count: 2 }, items: [expect.objectContaining({ source_reference_ids: [] }), expect.objectContaining({ source_reference_ids: [] })] })
+  expect(f.db.readStoryGraph('story_graph_search', { query: 'Atlas', scope: { kind: 'global' }, object_types: ['entity'] }))
+    .toMatchObject({ page: { has_more: false } })
+  expect(f.respond).toHaveBeenCalledTimes(calls)
 })
 
 it('stops oversized runtime responses with a readable error while preserving resumable progress', async () => {