fix(copilot): mark internal hook injections as agent-initiated

Apply the internal initiator marker to automated continuation, recovery, babysitter, stop-hook, and hook-message injections so Copilot attribution consistently sets x-initiator=agent for system-generated prompts.

src/hooks/todo-continuation-enforcer/continuation-injection.test.ts

@@ -2,18 +2,26 @@ declare const require: (name: string) => any
 const { describe, expect, test } = require("bun:test")
 
 import { injectContinuation } from "./continuation-injection"
+import { OMO_INTERNAL_INITIATOR_MARKER } from "../../shared/internal-initiator-marker"
 
 describe("injectContinuation", () => {
   test("inherits tools from resolved message info when reinjecting", async () => {
     // given
     let capturedTools: Record<string, boolean> | undefined
+    let capturedText: string | undefined
     const ctx = {
       directory: "/tmp/test",
       client: {
         session: {
           todo: async () => ({ data: [{ id: "1", content: "todo", status: "pending", priority: "high" }] }),
-          promptAsync: async (input: { body: { tools?: Record<string, boolean> } }) => {
+          promptAsync: async (input: {
+            body: {
+              tools?: Record<string, boolean>
+              parts?: Array<{ type: string; text: string }>
+            }
+          }) => {
             capturedTools = input.body.tools
+            capturedText = input.body.parts?.[0]?.text
             return {}
           },
         },
@@ -37,5 +45,6 @@ describe("injectContinuation", () => {
 
     // then
     expect(capturedTools).toEqual({ question: false, bash: true })
+    expect(capturedText).toContain(OMO_INTERNAL_INITIATOR_MARKER)
   })
 })

src/hooks/todo-continuation-enforcer/continuation-injection.ts

@@ -1,7 +1,11 @@
 import type { PluginInput } from "@opencode-ai/plugin"
 
 import type { BackgroundManager } from "../../features/background-agent"
-import { normalizeSDKResponse, resolveInheritedPromptTools } from "../../shared"
+import {
+  createInternalAgentTextPart,
+  normalizeSDKResponse,
+  resolveInheritedPromptTools,
+} from "../../shared"
 import {
   findNearestMessageWithFields,
   findNearestMessageWithFieldsFromSDK,
@@ -151,7 +155,7 @@ ${todoList}`
         agent: agentName,
         ...(model !== undefined ? { model } : {}),
         ...(inheritedTools ? { tools: inheritedTools } : {}),
-        parts: [{ type: "text", text: prompt }],
+        parts: [createInternalAgentTextPart(prompt)],
       },
       query: { directory: ctx.directory },
     })