Post-rebase reconciliation sweep:
- Sidebar: main's folded Sidebar.tsx/Sidebar.logic.ts adapted to v2 shells
  (latestRun/runtime naming, waiting status instead of monitoring), with
  subagent-thread filtering and main's pinned-reorder helpers re-exported
- Pinned drag reorder (#5581) ported into v2: thread.pin orderKey +
  thread.pin.reorder command, thread.pin-reordered event, Orchestrator fold,
  ProjectionStore/Maintenance, client-runtime commands and shell mapping
- Project favicon (#4849-era) and defaultThreadEnvMode flowed through v2
  contracts (OrchestrationProjectShell, application event payloads)
- ChatView: main's #5592 header props, pull-request right-panel surfaces,
  liveAgentCount badge (#5745) wired into the v2 panel layout
- enableAssistantStreaming -> enableLegacyTokenStreaming rename applied to
  v2 RunExecutionService and replay testkit
- Removed v1 zombies resurrected by the rebase (provider service/reaper/
  ingestion + v1 layer tests, server.test.ts, integration harness)
- routeTree: main's tree + branch's /settings/scheduled-tasks route
- Misc marker-sweep syntax repairs (rpc.ts, entities.ts, localApi.test.ts,
  rightPanelStore.test.ts, GitManager.test.ts, mobile model menu helpers)

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>