feat: add agentapi endpoint to report connections for audit (#16507)

This change adds a new `ReportConnection` endpoint to the `agentapi`.

The protocol version was bumped previously, so it has been omitted here.

This allows the agent to report connection events, for example when the
user connects to the workspace via SSH or VS Code.

Updates #15139

coderd/agentapi/api.go

@@ -19,6 +19,7 @@ import (
 	agentproto "github.com/coder/coder/v2/agent/proto"
 	"github.com/coder/coder/v2/coderd/agentapi/resourcesmonitor"
 	"github.com/coder/coder/v2/coderd/appearance"
+	"github.com/coder/coder/v2/coderd/audit"
 	"github.com/coder/coder/v2/coderd/database"
 	"github.com/coder/coder/v2/coderd/database/pubsub"
 	"github.com/coder/coder/v2/coderd/externalauth"
@@ -48,6 +49,7 @@ type API struct {
 	*ResourcesMonitoringAPI
 	*LogsAPI
 	*ScriptsAPI
+	*AuditAPI
 	*tailnet.DRPCService
 
 	mu sync.Mutex
@@ -66,6 +68,7 @@ type Options struct {
 	Database                          database.Store
 	NotificationsEnqueuer             notifications.Enqueuer
 	Pubsub                            pubsub.Pubsub
+	Auditor                           *atomic.Pointer[audit.Auditor]
 	DerpMapFn                         func() *tailcfg.DERPMap
 	TailnetCoordinator                *atomic.Pointer[tailnet.Coordinator]
 	StatsReporter                     *workspacestats.Reporter
@@ -174,6 +177,13 @@ func New(opts Options) *API {
 		Database: opts.Database,
 	}
 
+	api.AuditAPI = &AuditAPI{
+		AgentFn:  api.agent,
+		Auditor:  opts.Auditor,
+		Database: opts.Database,
+		Log:      opts.Log,
+	}
+
 	api.DRPCService = &tailnet.DRPCService{
 		CoordPtr:                opts.TailnetCoordinator,
 		Logger:                  opts.Log,