Show provider subagents in the subagents track (#2013)

* Add provider-owned subagent stream contract

* OpenCode provider: detect child sessions, attach adopted children to the hosting server, synthesize external turns

- Emit internal provider_child_session_detected / provider_session_deleted stream events from the global event stream (before the no-active-turn gate), including BFS hydration of existing descendants on subscribe
- Track child sessions in a registry mapping child session id -> hosting server url; resumeSession attaches via acquireExisting() so adopted children share the parent's server generation and keep receiving live events
- Synthesize external turns for adopted (externally driven) sessions so timeline, tool calls, and permission requests stream without a Paseo-initiated prompt
- Honor launchContext.env in resumeSession (acquireDedicated parity with createSession)
- Stop folding child tool parts into the parent's sub_agent action log; the parent row stays as a pointer

* Render provider subagents in workspace timelines

* fix provider subagent timeline reliability

* fix provider subagent lifecycle edge cases

* fix provider subagent event fidelity

* Fix provider subagent history fidelity

* Fix restored provider subagent state

* Fix provider subagent visibility edges

* Restore provider subagent timelines

* Page provider subagent history

* Forward subagent questions reliably

* fix(subagents): preserve OpenCode child context

* fix(subagents): harden provider timeline routing

* fix(subagents): preserve provider page continuity

* fix(subagents): retain live child prompts

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Co-authored-by: Omer <639682+omercnet@users.noreply.github.com>

packages/app/src/panels/register-panels.ts

@@ -5,6 +5,7 @@ import { filePanelRegistration } from "@/panels/file-panel";
 import { registerPanel } from "@/panels/panel-registry";
 import { setupPanelRegistration } from "@/panels/setup-panel";
 import { terminalPanelRegistration } from "@/panels/terminal-panel";
+import { providerSubagentPanelRegistration } from "@/panels/provider-subagent-panel";
 
 let panelsRegistered = false;
 
@@ -14,6 +15,7 @@ export function ensurePanelsRegistered(): void {
   }
   registerPanel(draftPanelRegistration);
   registerPanel(agentPanelRegistration);
+  registerPanel(providerSubagentPanelRegistration);
   registerPanel(setupPanelRegistration);
   registerPanel(terminalPanelRegistration);
   registerPanel(browserPanelRegistration);