[Flight] Don't drop debug info if there's only a readable debug channel (facebook#34304)

When the Flight Client is waiting for pending debug chunks, it drops the
debug info if there is no writable side of the debug channel defined.
However, it should instead check if there's no readable side defined.

Fixing this is not only important for browser clients that don't want or
need a return channel, but it's also crucial for server-side rendering,
because the Node and Edge clients only accept a readable side of the
debug channel. So they can't even define a noop writable side as a
workaround.

DiffTrain build for [9c2e2b8](facebook@9c2e2b8)

Author: pull[bot]

compiled/facebook-www/REVISION

@@ -1 +1 @@
-090777d78a4d61462dc984b9bba169edd3e7c088
+9c2e2b8475fb9d55fe47f55b007fba2d474e06f4

compiled/facebook-www/REVISION_TRANSFORMS

@@ -1 +1 @@
-090777d78a4d61462dc984b9bba169edd3e7c088
+9c2e2b8475fb9d55fe47f55b007fba2d474e06f4

compiled/facebook-www/React-dev.classic.js

@@ -1409,7 +1409,7 @@ __DEV__ &&
     exports.useTransition = function () {
       return resolveDispatcher().useTransition();
     };
-    exports.version = "19.2.0-www-classic-090777d7-20250822";
+    exports.version = "19.2.0-www-classic-9c2e2b84-20250827";
     "undefined" !== typeof __REACT_DEVTOOLS_GLOBAL_HOOK__ &&
       "function" ===
         typeof __REACT_DEVTOOLS_GLOBAL_HOOK__.registerInternalModuleStop &&

compiled/facebook-www/React-dev.modern.js

@@ -1409,7 +1409,7 @@ __DEV__ &&
     exports.useTransition = function () {
       return resolveDispatcher().useTransition();
     };
-    exports.version = "19.2.0-www-modern-090777d7-20250822";
+    exports.version = "19.2.0-www-modern-9c2e2b84-20250827";
     "undefined" !== typeof __REACT_DEVTOOLS_GLOBAL_HOOK__ &&
       "function" ===
         typeof __REACT_DEVTOOLS_GLOBAL_HOOK__.registerInternalModuleStop &&

compiled/facebook-www/React-prod.classic.js

@@ -600,4 +600,4 @@ exports.useSyncExternalStore = function (
 exports.useTransition = function () {
   return ReactSharedInternals.H.useTransition();
 };
-exports.version = "19.2.0-www-classic-090777d7-20250822";
+exports.version = "19.2.0-www-classic-9c2e2b84-20250827";

compiled/facebook-www/React-prod.modern.js

@@ -600,4 +600,4 @@ exports.useSyncExternalStore = function (
 exports.useTransition = function () {
   return ReactSharedInternals.H.useTransition();
 };
-exports.version = "19.2.0-www-modern-090777d7-20250822";
+exports.version = "19.2.0-www-modern-9c2e2b84-20250827";

compiled/facebook-www/React-profiling.classic.js

@@ -604,7 +604,7 @@ exports.useSyncExternalStore = function (
 exports.useTransition = function () {
   return ReactSharedInternals.H.useTransition();
 };
-exports.version = "19.2.0-www-classic-090777d7-20250822";
+exports.version = "19.2.0-www-classic-9c2e2b84-20250827";
 "undefined" !== typeof __REACT_DEVTOOLS_GLOBAL_HOOK__ &&
   "function" ===
     typeof __REACT_DEVTOOLS_GLOBAL_HOOK__.registerInternalModuleStop &&

compiled/facebook-www/React-profiling.modern.js

@@ -604,7 +604,7 @@ exports.useSyncExternalStore = function (
 exports.useTransition = function () {
   return ReactSharedInternals.H.useTransition();
 };
-exports.version = "19.2.0-www-modern-090777d7-20250822";
+exports.version = "19.2.0-www-modern-9c2e2b84-20250827";
 "undefined" !== typeof __REACT_DEVTOOLS_GLOBAL_HOOK__ &&
   "function" ===
     typeof __REACT_DEVTOOLS_GLOBAL_HOOK__.registerInternalModuleStop &&

compiled/facebook-www/ReactART-dev.classic.js

@@ -19588,10 +19588,10 @@ __DEV__ &&
     (function () {
       var internals = {
         bundleType: 1,
-        version: "19.2.0-www-classic-090777d7-20250822",
+        version: "19.2.0-www-classic-9c2e2b84-20250827",
         rendererPackageName: "react-art",
         currentDispatcherRef: ReactSharedInternals,
-        reconcilerVersion: "19.2.0-www-classic-090777d7-20250822"
+        reconcilerVersion: "19.2.0-www-classic-9c2e2b84-20250827"
       };
       internals.overrideHookState = overrideHookState;
       internals.overrideHookStateDeletePath = overrideHookStateDeletePath;
@@ -19625,7 +19625,7 @@ __DEV__ &&
     exports.Shape = Shape;
     exports.Surface = Surface;
     exports.Text = Text;
-    exports.version = "19.2.0-www-classic-090777d7-20250822";
+    exports.version = "19.2.0-www-classic-9c2e2b84-20250827";
     "undefined" !== typeof __REACT_DEVTOOLS_GLOBAL_HOOK__ &&
       "function" ===
         typeof __REACT_DEVTOOLS_GLOBAL_HOOK__.registerInternalModuleStop &&

compiled/facebook-www/ReactART-dev.modern.js

@@ -19359,10 +19359,10 @@ __DEV__ &&
     (function () {
       var internals = {
         bundleType: 1,
-        version: "19.2.0-www-modern-090777d7-20250822",
+        version: "19.2.0-www-modern-9c2e2b84-20250827",
         rendererPackageName: "react-art",
         currentDispatcherRef: ReactSharedInternals,
-        reconcilerVersion: "19.2.0-www-modern-090777d7-20250822"
+        reconcilerVersion: "19.2.0-www-modern-9c2e2b84-20250827"
       };
       internals.overrideHookState = overrideHookState;
       internals.overrideHookStateDeletePath = overrideHookStateDeletePath;
@@ -19396,7 +19396,7 @@ __DEV__ &&
     exports.Shape = Shape;
     exports.Surface = Surface;
     exports.Text = Text;
-    exports.version = "19.2.0-www-modern-090777d7-20250822";
+    exports.version = "19.2.0-www-modern-9c2e2b84-20250827";
     "undefined" !== typeof __REACT_DEVTOOLS_GLOBAL_HOOK__ &&
       "function" ===
         typeof __REACT_DEVTOOLS_GLOBAL_HOOK__.registerInternalModuleStop &&