fix: avoid connection logging crashes in agent (#20307)

- Ignore errors when reporting a connection from the server, just log
them instead
- Translate connection log IP `localhost` to `127.0.0.1` on both the
server and the agent

Note that the temporary fix for converting invalid IPs to localhost is
not required in main since the database no longer forbids NULL for the
IP column since https://github.com/coder/coder/pull/19788

Relates to #20194

coderd/agentapi/connectionlog_test.go

@@ -3,13 +3,11 @@ package agentapi_test
 import (
 	"context"
 	"database/sql"
-	"net"
 	"sync/atomic"
 	"testing"
 	"time"
 
 	"github.com/google/uuid"
-	"github.com/sqlc-dev/pqtype"
 	"github.com/stretchr/testify/require"
 	"go.uber.org/mock/gomock"
 	"google.golang.org/protobuf/types/known/timestamppb"
@@ -75,6 +73,9 @@ func TestConnectionLog(t *testing.T) {
 			action: agentproto.Connection_CONNECT.Enum(),
 			typ:    agentproto.Connection_JETBRAINS.Enum(),
 			time:   dbtime.Now(),
+			// Sometimes, JetBrains clients report as localhost, see
+			// https://github.com/coder/coder/issues/20194
+			ip: "localhost",
 		},
 		{
 			name:   "Reconnecting PTY Connect",
@@ -129,6 +130,12 @@ func TestConnectionLog(t *testing.T) {
 				},
 			})
 
+			expectedIPRaw := tt.ip
+			if expectedIPRaw == "localhost" {
+				expectedIPRaw = "127.0.0.1"
+			}
+			expectedIP := database.ParseIP(expectedIPRaw)
+
 			require.True(t, connLogger.Contains(t, database.UpsertConnectionLogParams{
 				Time:             dbtime.Time(tt.time).In(time.UTC),
 				OrganizationID:   workspace.OrganizationID,
@@ -146,7 +153,7 @@ func TestConnectionLog(t *testing.T) {
 					Int32: tt.status,
 					Valid: *tt.action == agentproto.Connection_DISCONNECT,
 				},
-				Ip:   pqtype.Inet{Valid: true, IPNet: net.IPNet{IP: net.ParseIP(tt.ip), Mask: net.CIDRMask(32, 32)}},
+				Ip:   expectedIP,
 				Type: agentProtoConnectionTypeToConnectionLog(t, *tt.typ),
 				DisconnectReason: sql.NullString{
 					String: tt.reason,