Merge branch 'main' into dev

Surgical merge of 74 commits from main into dev. Key features ported:

- Provider visibility gating (appVersion filtering for Pi/Copilot)
- Pi agent provider + Copilot re-enabled
- Provider-declared features system (Codex fast mode)
- Workspace dedup by worktree root (adapted to integer IDs)
- Bulk close archiving fix for stored agents
- Agent creation timeout increase to 60s
- Audio/voice crash fixes (external buffer copies)
- Multi-host setup fix
- Reload agent tab action

Dev architecture preserved: SQLite storage, service proxy,
workspace setup dialog, hover cards, removed launcher tabs.

packages/app/src/stores/session-store.ts

@@ -10,6 +10,7 @@ import type {
   AgentPermissionResponse,
   AgentPermissionRequest,
   AgentSessionConfig,
+  AgentFeature,
   AgentProvider,
   AgentMode,
   AgentCapabilityFlags,
@@ -100,6 +101,7 @@ export interface Agent {
   title: string | null;
   cwd: string;
   model: string | null;
+  features?: AgentFeature[];
   thinkingOptionId?: string | null;
   requiresAttention?: boolean;
   attentionReason?: "finished" | "error" | "permission" | null;