agent: drain FIFO after interrupted/failed turns

Fix holes where queued prompts were orphaned:
- After turn loop exits (interrupt, toolsrv unavailable), drain remaining FIFO items
- On panic recovery, pop next FIFO item and re-submit in a new goroutine
- fifo file write triggers Submit when agent is idle

cmd/olliesrv/internal/agent/turn.go

@@ -30,6 +30,11 @@ func (ag *Agent) Submit(ctx context.Context, input string) {
 			}
 			ag.SetState("idle")
 			ag.emit(Event{Role: "error", Content: fmt.Sprintf("%v", r)})
+			// Re-submit next FIFO item in a new goroutine so queued
+			// prompts aren't orphaned by the panic.
+			if next, ok := ag.fifo.Pop(); ok {
+				go ag.Submit(ctx, next)
+			}
 		}
 	}()
 	ag.log.Debug("Agent.Submit() input_len=%d running=%v", len(input), ag.IsRunning())
@@ -63,6 +68,17 @@ func (ag *Agent) Submit(ctx context.Context, input string) {
 	for input != "" && ctx.Err() == nil {
 		input = ag.executeTurn(ctx, input)
 	}
+	// Drain any remaining FIFO items (covers cases where executeTurn
+	// returned "" early: interrupt, toolsrv unavailable, etc.).
+	for ctx.Err() == nil {
+		next, ok := ag.fifo.Pop()
+		if !ok {
+			break
+		}
+		for next != "" && ctx.Err() == nil {
+			next = ag.executeTurn(ctx, next)
+		}
+	}
 }
 
 // executeTurn runs a single agent turn and returns the next prompt to execute,

cmd/olliesrv/internal/fs/spec.go

@@ -373,6 +373,15 @@ func buildAgentChildren(a *agent.Agent, s *session.Session) []virtfs.FsNodeDecl
 					return nil
 				}
 				a.Queue(input)
+				// If the agent is idle, trigger processing.
+				if !a.IsRunning() {
+					go func() {
+						if next, ok := a.PopQueue(); ok {
+							a.Submit(s.Ctx, next)
+							a.EnsureTrailingNewline()
+						}
+					}()
+				}
 				return nil
 			}),
 			virtfs.Read(func() ([]byte, error) {