fix(telegram): grant in-chat members regardless of reported can_send

The CanSendMessages loop-guard skipped exactly the stuck case — a restricted
member whose chat_member event reports can_send=true yet who cannot actually
write. Replace it with a precise loop guard (skip only the bot's own restrict
action, i.e. the update whose performer is the bot) and grant any eligible
in-chat member (member or restricted) otherwise. Also log the new member's
can_send, is_member and the actor id for full visibility.

platform/telegram/internal/bot/chat_test.go

@@ -3,6 +3,7 @@ package bot
 import (
 	"context"
 	"encoding/json"
+	"fmt"
 	"io"
 	"net/http"
 	"net/http/httptest"
@@ -13,7 +14,10 @@ import (
 	"go.uber.org/zap"
 )
 
-const testChatID = 555
+const (
+	testChatID = 555
+	botSelfID  = 111111 // the bot's own id in tests (for the loop guard)
+)
 
 // chatAPI is a fake Bot API for the chat-gating tests: it answers getMe, returns a
 // scripted getChatMember status, and records restrictChatMember calls.
@@ -59,6 +63,7 @@ func newChatBot(t *testing.T, api *chatAPI) *Bot {
 	if err != nil {
 		t.Fatalf("new bot: %v", err)
 	}
+	b.botID = botSelfID // normally set at startup; the chat_member updates default actor 0 != this
 	return b
 }
 
@@ -109,14 +114,22 @@ func TestHandleChatMemberGrantsEligibleMemberJoin(t *testing.T) {
 }
 
 func TestHandleChatMemberGrantsRestrictedMember(t *testing.T) {
-	// A default-deny group reports a present member as restricted with no send right —
-	// the real-world case. Both a fresh join (left->restricted) and an already-present
-	// restricted member (restricted->restricted) must be granted when eligible.
-	for _, oldType := range []models.ChatMemberType{models.ChatMemberTypeLeft, models.ChatMemberTypeRestricted} {
-		t.Run(string(oldType), func(t *testing.T) {
+	// A default-deny group reports a present member as restricted — the real-world case.
+	// A fresh join (left->restricted) or an already-present restricted member
+	// (restricted->restricted), and regardless of the reported can_send (which can be
+	// misleading), an eligible member is granted.
+	for _, tc := range []struct {
+		old     models.ChatMemberType
+		canSend bool
+	}{
+		{models.ChatMemberTypeLeft, false},
+		{models.ChatMemberTypeRestricted, false},
+		{models.ChatMemberTypeRestricted, true},
+	} {
+		t.Run(fmt.Sprintf("%s_cansend=%v", tc.old, tc.canSend), func(t *testing.T) {
 			api := &chatAPI{}
 			b := eligibleBot(t, api, true, nil)
-			b.handleChatMember(context.Background(), restrictedUpdate(testChatID, 777, oldType, false))
+			b.handleChatMember(context.Background(), restrictedUpdate(testChatID, 777, tc.old, tc.canSend))
 			if len(api.restricts) != 1 || !api.restricts[0].canSend {
 				t.Fatalf("restricts = %+v, want one grant for a restricted member", api.restricts)
 			}
@@ -124,14 +137,16 @@ func TestHandleChatMemberGrantsRestrictedMember(t *testing.T) {
 	}
 }
 
-func TestHandleChatMemberSkipsAlreadyAllowed(t *testing.T) {
-	// The bot's own grant re-fires a chat_member event (restricted, can_send=true); it
-	// must not loop into another grant.
+func TestHandleChatMemberSkipsBotsOwnAction(t *testing.T) {
+	// The bot's own grant re-fires a chat_member update performed by the bot; it must be
+	// skipped so a grant never loops into another grant.
 	api := &chatAPI{}
 	b := eligibleBot(t, api, true, nil)
-	b.handleChatMember(context.Background(), restrictedUpdate(testChatID, 777, models.ChatMemberTypeRestricted, true))
+	upd := restrictedUpdate(testChatID, 777, models.ChatMemberTypeRestricted, false)
+	upd.From = models.User{ID: botSelfID}
+	b.handleChatMember(context.Background(), upd)
 	if len(api.restricts) != 0 {
-		t.Fatalf("restricts = %+v, want none for an already-allowed member (no loop)", api.restricts)
+		t.Fatalf("restricts = %+v, want none for the bot's own action (no loop)", api.restricts)
 	}
 }