feat(command): extend slash command system with new commands and UX improvements

Add 9 new command groups (/model, /memory, /search, /browser, /usage,
/email, /heartbeat, /skill, /fs) and improve existing commands by hiding
internal UUIDs, resolving IDs to human-readable names in /settings, and
switching /schedule to name-based references.

internal/command/parser.go

@@ -0,0 +1,98 @@
+package command
+
+import (
+	"errors"
+	"strings"
+)
+
+// ParsedCommand holds the parsed components of a slash command.
+type ParsedCommand struct {
+	Resource string   // e.g. "schedule", "subagent", "help"
+	Action   string   // e.g. "list", "get", "create"
+	Args     []string // remaining positional arguments
+}
+
+// Parse parses a raw command string into its components.
+// Expected format: /resource [action] [args...]
+func Parse(text string) (ParsedCommand, error) {
+	text = strings.TrimSpace(text)
+	if !strings.HasPrefix(text, "/") {
+		return ParsedCommand{}, errors.New("command must start with /")
+	}
+	text = text[1:] // strip leading /
+
+	tokens := tokenize(text)
+	if len(tokens) == 0 {
+		return ParsedCommand{}, errors.New("empty command")
+	}
+
+	resource := strings.ToLower(tokens[0])
+	// Strip Telegram-style @botname suffix (e.g. "help@MemohBot" -> "help").
+	if idx := strings.IndexByte(resource, '@'); idx > 0 {
+		resource = resource[:idx]
+	}
+
+	cmd := ParsedCommand{
+		Resource: resource,
+	}
+	if len(tokens) > 1 {
+		cmd.Action = strings.ToLower(tokens[1])
+	}
+	if len(tokens) > 2 {
+		cmd.Args = tokens[2:]
+	}
+	return cmd, nil
+}
+
+// ExtractCommandText finds and extracts a slash command from text that may
+// contain a leading @mention (e.g. "@BotName /help arg1" -> "/help arg1").
+// Returns the command text starting with "/", or empty string if none found.
+func ExtractCommandText(text string) string {
+	trimmed := strings.TrimSpace(text)
+	if strings.HasPrefix(trimmed, "/") {
+		return trimmed
+	}
+	// Look for " /" pattern — a slash preceded by whitespace.
+	idx := strings.Index(trimmed, " /")
+	if idx >= 0 {
+		return strings.TrimSpace(trimmed[idx+1:])
+	}
+	return ""
+}
+
+// tokenize splits a command string respecting quoted segments.
+func tokenize(input string) []string {
+	var tokens []string
+	var current strings.Builder
+	inQuote := false
+	quoteChar := byte(0)
+
+	for i := 0; i < len(input); i++ {
+		ch := input[i]
+		if inQuote {
+			if ch == quoteChar {
+				inQuote = false
+				continue
+			}
+			current.WriteByte(ch)
+			continue
+		}
+		if ch == '"' || ch == '\'' {
+			inQuote = true
+			quoteChar = ch
+			continue
+		}
+		if ch == ' ' || ch == '\t' {
+			if current.Len() > 0 {
+				tokens = append(tokens, current.String())
+				current.Reset()
+			}
+			continue
+		}
+		current.WriteByte(ch)
+	}
+	if current.Len() > 0 {
+		tokens = append(tokens, current.String())
+	}
+	return tokens
+}