Add tm_server with SQLite, Svelte UI, and task-master TUI sync.

Introduces the web backend (auth, RBAC, project tokens, revisions),
YouTrack-or-taskmaster backend choice in the TUI, and a first-pass
embedded Svelte UI. The frontend is functional but needs a major rework.

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

internal/server/import_json.go

@@ -0,0 +1,72 @@
+package server
+
+import (
+	"fmt"
+
+	"task/internal/project"
+	"task/internal/ticket"
+)
+
+// ImportJSONDataDir copies projects/tickets/time from a local JSON DataDir into SQLite.
+func (s *Server) ImportJSONDataDir(dataDir string, ownerUserID string) error {
+	ps := project.NewDirStore(dataDir)
+	ts := ticket.NewJSONStore(dataDir)
+	timeStore := ticket.NewJSONTimeStore(dataDir)
+
+	projects, err := ps.List()
+	if err != nil {
+		return err
+	}
+	for _, p := range projects {
+		if err := s.Projects.Ensure(p.ID); err != nil {
+			return fmt.Errorf("project %s: %w", p.ID, err)
+		}
+		if ownerUserID != "" {
+			_ = s.DB.SetMember(p.ID, ownerUserID, "owner")
+		}
+		meta, err := ps.LoadMeta(p.ID)
+		if err != nil {
+			return err
+		}
+		if meta.YouTrack != nil && meta.YouTrack.Configured() {
+			if err := s.Projects.SaveMeta(p.ID, meta); err != nil {
+				return fmt.Errorf("meta %s: %w", p.ID, err)
+			}
+		}
+		tickets, err := ts.List(p.ID)
+		if err != nil {
+			return err
+		}
+		for _, t := range tickets {
+			if _, err := s.Tickets.Get(t.ID); err == nil {
+				continue // already imported
+			}
+			if _, err := s.Tickets.Create(t); err != nil {
+				return fmt.Errorf("ticket %s: %w", t.ID, err)
+			}
+			_, _ = s.DB.AppendRevision("ticket", t.ID, p.ID, "import", ownerUserID, t)
+		}
+	}
+
+	entries, err := timeStore.List()
+	if err != nil {
+		return err
+	}
+	existing, _ := s.Times.List()
+	have := map[string]bool{}
+	for _, e := range existing {
+		have[e.ID] = true
+	}
+	for _, e := range entries {
+		if have[e.ID] {
+			continue
+		}
+		if _, err := s.Times.Create(e); err != nil {
+			return fmt.Errorf("time %s: %w", e.ID, err)
+		}
+	}
+	if active, err := timeStore.LoadActiveTimer(); err == nil && active != nil {
+		_ = s.Times.SaveActiveTimer(active)
+	}
+	return nil
+}