feat: NOFXi Agent integrated into NOFX core

This is the key architectural change: NOFXi is no longer a separate
sub-project in nofxi/, but a first-class module in agent/ that sits
on top of NOFX's existing engine.

agent/ package:
- agent.go: Core orchestrator, directly uses NOFX's TraderManager,
  Store, and Market packages. No wrapper/bridge needed.
- brain.go: Proactive intelligence (news scan, market briefs, signal handling)
- sentinel.go: Market anomaly detection (price breakout, volume spike, funding rate)
- scheduler.go: Daily reports, position risk checks
- router.go: Intent routing for natural language (中/英 bilingual)
- i18n.go: Full Chinese/English message catalog
- web.go: Agent REST API on :8900 (chat, klines, ticker)

main.go changes:
- Banner: NOFX → NOFXi
- Agent auto-starts with NOFX (sentinel + brain + scheduler + web)
- Zero breaking changes to existing NOFX functionality

Key difference from old nofxi/:
- Agent reads LIVE data from TraderManager (positions, balances, status)
- Uses market.Get() for full technical indicators (EMA/MACD/RSI/BB)
- No duplicate code — kernel, trader, store all used directly
- Old nofxi/ sub-project will be removed once migration is verified

Architecture:
  NOFX (engine) → kernel + trader + market + store + mcp + telegram
  NOFXi (brain) → agent/ package → uses all of the above

agent/router.go

@@ -0,0 +1,102 @@
+package agent
+
+import (
+	"regexp"
+	"strings"
+)
+
+type IntentType int
+
+const (
+	IntentChat     IntentType = iota
+	IntentTrade
+	IntentQuery
+	IntentAnalyze
+	IntentSettings
+	IntentHelp
+	IntentStatus
+	IntentWatch
+	IntentStrategy
+)
+
+type Intent struct {
+	Type   IntentType
+	Params map[string]string
+	Raw    string
+}
+
+type Router struct {
+	tradePatterns   []*regexp.Regexp
+	queryPatterns   []*regexp.Regexp
+	analyzePatterns []*regexp.Regexp
+}
+
+func NewRouter() *Router {
+	return &Router{
+		tradePatterns: []*regexp.Regexp{
+			regexp.MustCompile(`(?i)(buy|sell|long|short|open|close)\s+(.+)`),
+			regexp.MustCompile(`(?i)(做多|做空|买入|卖出|开仓|平仓)\s*(.+)`),
+		},
+		queryPatterns: []*regexp.Regexp{
+			regexp.MustCompile(`(?i)(position|balance|pnl|profit|loss|持仓|余额|盈亏|trader|交易员)`),
+		},
+		analyzePatterns: []*regexp.Regexp{
+			regexp.MustCompile(`(?i)(analyze|analysis|分析|看看)\s+(.+)`),
+			regexp.MustCompile(`(?i)(what.*think|怎么看|你觉得)\s*(.+)?`),
+		},
+	}
+}
+
+func (r *Router) Route(text string) Intent {
+	text = strings.TrimSpace(text)
+
+	if strings.HasPrefix(text, "/") {
+		return r.routeCommand(text)
+	}
+
+	for _, p := range r.tradePatterns {
+		if m := p.FindStringSubmatch(text); m != nil {
+			return Intent{Type: IntentTrade, Params: map[string]string{"action": strings.ToLower(m[1]), "detail": m[2]}, Raw: text}
+		}
+	}
+	for _, p := range r.queryPatterns {
+		if p.MatchString(text) {
+			return Intent{Type: IntentQuery, Raw: text}
+		}
+	}
+	for _, p := range r.analyzePatterns {
+		if m := p.FindStringSubmatch(text); m != nil {
+			d := ""
+			if len(m) > 2 { d = m[2] }
+			return Intent{Type: IntentAnalyze, Params: map[string]string{"detail": d}, Raw: text}
+		}
+	}
+
+	return Intent{Type: IntentChat, Raw: text}
+}
+
+func (r *Router) routeCommand(text string) Intent {
+	cmd := strings.ToLower(strings.Fields(text)[0])
+	parts := strings.SplitN(text, " ", 2)
+	detail := ""
+	if len(parts) > 1 { detail = parts[1] }
+
+	switch cmd {
+	case "/start", "/help":
+		return Intent{Type: IntentHelp, Raw: text}
+	case "/status":
+		return Intent{Type: IntentStatus, Raw: text}
+	case "/buy", "/sell", "/long", "/short", "/open", "/close":
+		return Intent{Type: IntentTrade, Params: map[string]string{"action": strings.TrimPrefix(cmd, "/"), "detail": detail}, Raw: text}
+	case "/positions", "/balance", "/pnl", "/traders":
+		return Intent{Type: IntentQuery, Raw: text}
+	case "/analyze":
+		return Intent{Type: IntentAnalyze, Params: map[string]string{"detail": detail}, Raw: text}
+	case "/watch", "/unwatch":
+		return Intent{Type: IntentWatch, Raw: text}
+	case "/strategy":
+		return Intent{Type: IntentStrategy, Raw: text}
+	default:
+		return Intent{Type: IntentChat, Raw: text}
+	}
+}