feat(controller): add source for command handling.

feat(telegram): switch message type to markdown
feat(controller): add welcome message for telegram bot.

internal/controller/trigger.go

@@ -5,6 +5,70 @@ import (
 	"strings"
 )
 
+// Trigger validates an incoming command against the pipe's authorization
+// config (trusted groups / admins) and, if authorized, processes it through
+// RouteCommand. It returns the response text to reply with; an empty response means
+// the command was discarded.
+//
+// All command handling across pipes is unified here: pipes only decide whether
+// a received message is a command, then hand the complete command over.
+func (m *Manager) Trigger(cmd Command, trustedGroups, admins []string, listenMethod string) (string, error) {
+	// Check whether the command arrived in a group or a private chat.
+	if cmd.ChatType == "group" {
+		// Group commands are only honored from trusted groups, otherwise discard.
+		if !IsTrustedGroup(cmd.ChatID, trustedGroups) {
+			return "", nil
+		}
+	}
+
+	// Commands that require special permission must be sent by an admin.
+	if IsAdminCommand(cmd.Command) {
+		if !IsAdmin(cmd.SenderID, admins) {
+			return "", nil
+		}
+	}
+
+	response, err := m.RouteCommand(cmd)
+	if err != nil {
+		return "", err
+	}
+
+	// In "at" listen mode, give feedback for unknown commands.
+	if response == "" && listenMethod == "at" {
+		return "Unknown command: /" + cmd.Command, nil
+	}
+	return response, nil
+}
+
+// RouteCommand processes a parsed bot command and returns the response text.
+// The actual command execution for every pipe is unified here.
+func (m *Manager) RouteCommand(cmd Command) (string, error) {
+	if cmd.Source == "telegram"{
+		switch cmd.Command {
+		case "start":
+			return telegram_handleStart()
+		}
+	}
+	switch cmd.Command {
+	case "help":
+		return handleHelp()
+	case "list":
+		return handleList()
+	case "status":
+		return handleStatus(cmd)
+	case "shutdown":
+		return handleShutdown(cmd)
+	case "reboot":
+		return handleReboot(cmd)
+	case "run":
+		return handleRun(cmd)
+	case "info":
+		return handleInfo(cmd)
+	default:
+		return "", nil
+	}
+}
+
 // ParseCommand parses a raw message text into a Command.
 // Format: /{{command}} {{args...}}
 func ParseCommand(rawText string) (cmd Command, ok bool) {