cdbg: make endpoint deployment failure more transparent (#1883)

* add retry + timeout + intercept grpc logs

* LogStateChanges inside grplog pkg

* remove retry and tj/assert

* rename nit

* Update debugd/internal/cdbg/cmd/deploy.go

Co-authored-by: Paul Meyer <49727155+katexochen@users.noreply.github.com>

* Update debugd/internal/cdbg/cmd/deploy.go

Co-authored-by: Paul Meyer <49727155+katexochen@users.noreply.github.com>

* paul feedback

* return waitFn instead of WaitGroup

* Revert "return waitFn instead of WaitGroup"

This reverts commit 45700f30e341ce3af509b687febbc0125f7ddb38.

* log routine inside debugd constructor

* test doubles names

* Update debugd/internal/cdbg/cmd/deploy.go

Co-authored-by: Paul Meyer <49727155+katexochen@users.noreply.github.com>

* fix newDebugClient closeFn

---------

Co-authored-by: Paul Meyer <49727155+katexochen@users.noreply.github.com>

internal/grpc/grpclog/grpclog.go

@@ -0,0 +1,53 @@
+/*
+Copyright (c) Edgeless Systems GmbH
+
+SPDX-License-Identifier: AGPL-3.0-only
+*/
+
+// grpclog provides a logging utilities for gRPC.
+package grpclog
+
+import (
+	"context"
+	"sync"
+
+	"google.golang.org/grpc/connectivity"
+	"google.golang.org/grpc/peer"
+)
+
+// PeerAddrFromContext returns a peer's address from context, or "unknown" if not found.
+func PeerAddrFromContext(ctx context.Context) string {
+	p, ok := peer.FromContext(ctx)
+	if !ok {
+		return "unknown"
+	}
+	return p.Addr.String()
+}
+
+// LogStateChangesUntilReady logs the state changes of a gRPC connection.
+func LogStateChangesUntilReady(ctx context.Context, conn getStater, log debugLog, wg *sync.WaitGroup, isReadyCallback func()) {
+	wg.Add(1)
+	go func() {
+		defer wg.Done()
+		state := conn.GetState()
+		log.Debugf("Connection state started as %s", state)
+		for ; state != connectivity.Ready && conn.WaitForStateChange(ctx, state); state = conn.GetState() {
+			log.Debugf("Connection state changed to %s", state)
+		}
+		if state == connectivity.Ready {
+			log.Debugf("Connection ready")
+			isReadyCallback()
+		} else {
+			log.Debugf("Connection state ended with %s", state)
+		}
+	}()
+}
+
+type getStater interface {
+	GetState() connectivity.State
+	WaitForStateChange(context.Context, connectivity.State) bool
+}
+
+type debugLog interface {
+	Debugf(format string, args ...any)
+}