feat(tui): add the lazygit-style three-pane interface

Topics, messages, and message detail in three panes, with filtering, publishing, adding topics, a raw JSON view, history restore, and open-link support.

internal/tui/cmd.go

@@ -0,0 +1,36 @@
+package tui
+
+import (
+	"context"
+	"os/exec"
+	"time"
+
+	tea "charm.land/bubbletea/v2"
+
+	"lazyntfy/internal/config"
+	"lazyntfy/internal/ntfy"
+)
+
+type publishDone struct{ err error }
+type openDone struct{ err error }
+
+func publishCmd(client *ntfy.Client, sub config.Sub, req ntfy.PublishRequest) tea.Cmd {
+	return func() tea.Msg {
+		ctx, cancel := context.WithTimeout(context.Background(), 20*time.Second)
+		defer cancel()
+		return publishDone{err: client.Publish(ctx, sub.Origin, sub.Name, sub.Auth, req)}
+	}
+}
+
+func openCmd(raw string) tea.Cmd {
+	return func() tea.Msg {
+		return openDone{err: openURL(raw)}
+	}
+}
+
+func openURL(raw string) error {
+	if err := validateURL(raw); err != nil {
+		return err
+	}
+	return exec.Command("xdg-open", raw).Start()
+}