Add local JSON daemon and route TUI/CLI through it.

A per-DataDir background process owns ticket JSON, history, and sync so
multiple TUI instances stay consistent; MCP token APIs are ready for phase 2.

Co-authored-by: Cursor <cursoragent@cursor.com>

internal/daemon/client/executor.go

@@ -0,0 +1,100 @@
+package client
+
+import (
+	"fmt"
+	"net/http"
+	"net/url"
+
+	"task/internal/command"
+	"task/internal/ticket"
+)
+
+// Executor implements command.Executor via daemon mutation endpoints.
+type Executor struct{ c *Client }
+
+func (c *Client) Executor() *Executor { return &Executor{c: c} }
+
+func (e *Executor) Do(cmd command.Command) error {
+	switch c := cmd.(type) {
+	case *command.CreateTicket:
+		var out ticket.Ticket
+		if err := e.c.do(http.MethodPost, "/v1/tickets", c.Ticket, &out); err != nil {
+			return err
+		}
+		c.Ticket = out
+		return nil
+	case *command.UpdateTicket:
+		return e.c.do(http.MethodPatch, "/v1/tickets/"+url.PathEscape(c.After.ID), c.After, nil)
+	case *command.DeleteTicket:
+		return e.c.do(http.MethodDelete, "/v1/tickets/"+url.PathEscape(c.Snapshot.ID), nil, nil)
+	case *command.MoveTicket:
+		var out ticket.Ticket
+		if err := e.c.do(http.MethodPost, "/v1/tickets/"+url.PathEscape(c.Before.ID)+"/move", map[string]string{
+			"toProjectId": c.After.ProjectID,
+		}, &out); err != nil {
+			return err
+		}
+		c.After = out
+		return nil
+	case *command.AddTimeEntry:
+		var out ticket.TimeEntry
+		if err := e.c.do(http.MethodPost, "/v1/time", c.Entry, &out); err != nil {
+			return err
+		}
+		c.Entry = out
+		return nil
+	case *command.RemoveTimeEntry:
+		return e.c.do(http.MethodDelete, "/v1/time/"+url.PathEscape(c.Snapshot.ID), nil, nil)
+	case *command.UpdateTimeEntry:
+		return e.c.do(http.MethodPatch, "/v1/time/"+url.PathEscape(c.After.ID), c.After, nil)
+	default:
+		return fmt.Errorf("unsupported command type %T", cmd)
+	}
+}
+
+func (e *Executor) Undo() error {
+	return e.c.do(http.MethodPost, "/v1/undo", map[string]any{}, nil)
+}
+
+func (e *Executor) Redo() error {
+	return e.c.do(http.MethodPost, "/v1/redo", map[string]any{}, nil)
+}
+
+func (e *Executor) CanUndo() bool {
+	st, err := e.status()
+	if err != nil {
+		return false
+	}
+	return st.CanUndo
+}
+
+func (e *Executor) CanRedo() bool {
+	st, err := e.status()
+	if err != nil {
+		return false
+	}
+	return st.CanRedo
+}
+
+func (e *Executor) LastUndoName() string {
+	st, _ := e.status()
+	return st.LastUndoName
+}
+
+func (e *Executor) LastRedoName() string {
+	st, _ := e.status()
+	return st.LastRedoName
+}
+
+type historyStatus struct {
+	CanUndo      bool   `json:"canUndo"`
+	CanRedo      bool   `json:"canRedo"`
+	LastUndoName string `json:"lastUndoName"`
+	LastRedoName string `json:"lastRedoName"`
+}
+
+func (e *Executor) status() (historyStatus, error) {
+	var st historyStatus
+	err := e.c.do(http.MethodGet, "/v1/history", nil, &st)
+	return st, err
+}