refactor: replace raw SQL with repository interfaces in entranceserver and API server

Extract all direct database calls from entranceserver (2 calls) and
API server (17 calls) into typed repository interfaces with PostgreSQL
implementations, matching the pattern established in signserver and
channelserver.

Entranceserver: EntranceServerRepo, EntranceSessionRepo
API server: APIUserRepo, APICharacterRepo, APISessionRepo

Also fix the 3 remaining fmt.Sprintf calls inside logger invocations
in handlers_commands.go and handlers_stage.go, replacing them with
structured zap fields.

Unskip 5 TestNewAuthData* tests that previously required a real
database — they now run with mock repos.

server/entranceserver/make_resp_test.go

@@ -113,6 +113,99 @@ func TestClanMemberLimitsBoundsChecking(t *testing.T) {
 }
 
 
+// TestEncodeServerInfo_WithMockRepo tests encodeServerInfo with a mock server repo
+func TestEncodeServerInfo_WithMockRepo(t *testing.T) {
+	config := &cfg.Config{
+		RealClientMode: cfg.Z1,
+		Host:           "127.0.0.1",
+		Entrance: cfg.Entrance{
+			Enabled: true,
+			Port:    53310,
+			Entries: []cfg.EntranceServerInfo{
+				{
+					Name:        "TestServer",
+					Description: "Test",
+					IP:          "127.0.0.1",
+					Type:        0,
+					Recommended: 0,
+					AllowedClientFlags: 0xFFFFFFFF,
+					Channels: []cfg.EntranceChannelInfo{
+						{
+							Port:       54001,
+							MaxPlayers: 100,
+						},
+					},
+				},
+			},
+		},
+		GameplayOptions: cfg.GameplayOptions{
+			ClanMemberLimits: [][]uint8{{1, 60}},
+		},
+	}
+
+	server := &Server{
+		logger:      zap.NewNop(),
+		erupeConfig: config,
+		serverRepo:  &mockEntranceServerRepo{currentPlayers: 42},
+	}
+
+	result := encodeServerInfo(config, server, true)
+	if len(result) == 0 {
+		t.Error("encodeServerInfo returned empty result")
+	}
+}
+
+// TestMakeUsrResp_WithMockRepo tests makeUsrResp with a mock session repo
+func TestMakeUsrResp_WithMockRepo(t *testing.T) {
+	config := &cfg.Config{
+		RealClientMode: cfg.Z1,
+	}
+
+	server := &Server{
+		logger:      zap.NewNop(),
+		erupeConfig: config,
+		sessionRepo: &mockEntranceSessionRepo{serverID: 1234},
+	}
+
+	// Build a minimal USR request packet:
+	// 4 bytes ALL+ prefix, 1 byte 0x00, 2 bytes entry count, then 4 bytes per entry (char ID)
+	pkt := []byte{
+		'A', 'L', 'L', '+',
+		0x00,
+		0x00, 0x01, // 1 entry
+		0x00, 0x00, 0x00, 0x01, // char_id = 1
+	}
+
+	result := makeUsrResp(pkt, server)
+	if len(result) == 0 {
+		t.Error("makeUsrResp returned empty result")
+	}
+}
+
+// TestMakeUsrResp_NilSessionRepo tests makeUsrResp when sessionRepo is nil
+func TestMakeUsrResp_NilSessionRepo(t *testing.T) {
+	config := &cfg.Config{
+		RealClientMode: cfg.Z1,
+	}
+
+	server := &Server{
+		logger:      zap.NewNop(),
+		erupeConfig: config,
+	}
+
+	pkt := []byte{
+		'A', 'L', 'L', '+',
+		0x00,
+		0x00, 0x01,
+		0x00, 0x00, 0x00, 0x01,
+	}
+
+	result := makeUsrResp(pkt, server)
+	if len(result) == 0 {
+		t.Error("makeUsrResp returned empty result")
+	}
+}
+
 // TestEncodeServerInfo_MissingSecondColumnClanMemberLimits tests accessing [last][1] when [last] is too small
 // Previously panicked: runtime error: index out of range [1]
 // After fix: Should handle missing column gracefully with default value (60)