feat(backthink): 后台自主思考（heartbeat+事件触发 + 打扰决策 fail-closed + 主动推送活跃→IM 兜底 + 限制 + 思考记录）

internal/services/backthink/thinker.go

@@ -0,0 +1,45 @@
+package backthink
+
+import (
+	"context"
+	"fmt"
+
+	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/loop"
+	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/model"
+)
+
+// LoopThinker adapts a *loop.Loop into a Thinker. It is the production wiring
+// that lets a background pass drive the full tool loop (memory injection, model
+// steps, tool calls such as IoT/calendar/reminders) without the service knowing
+// the loop's concrete shape.
+type LoopThinker struct {
+	loop *loop.Loop
+}
+
+// NewLoopThinker wraps l as a Thinker.
+func NewLoopThinker(l *loop.Loop) *LoopThinker { return &LoopThinker{loop: l} }
+
+// Think runs one unattended think through the wrapped loop and returns the
+// conclusion text. It returns ErrNoLoop when no loop was injected.
+func (t *LoopThinker) Think(ctx context.Context, sessionID, trigger string) (string, error) {
+	if t.loop == nil {
+		return "", ErrNoLoop
+	}
+	messages := []model.Message{model.TextMessage(model.RoleUser, backgroundPrompt(trigger))}
+	res, err := t.loop.Run(ctx, sessionID, messages)
+	if err != nil {
+		return "", fmt.Errorf("backthink: think: %w", err)
+	}
+	return res.Text, nil
+}
+
+// backgroundPrompt is the instruction handed to the runtime for one unattended
+// thought. It explicitly avoids asking for a chat-style message to the user.
+func backgroundPrompt(trigger string) string {
+	return "[background autonomous reflection]\n" +
+		"Trigger: " + trigger + "\n" +
+		"Review recent context, device states, calendar and reminders. Decide " +
+		"whether anything is worth proactively telling the owner. If nothing " +
+		"matters, conclude \"nothing to report\". Keep the conclusion to one or " +
+		"two sentences. Do not produce a chat-style message to the user."
+}