Keep a module's report under a bounded context the client's stop does not cancel (issue 774)

The test of a node coming back stops the client before the report of zsh is kept; the cancelled Put left s.applied without zsh, so leftModules never removed it (2 of 20 runs failed under -race, also at origin/main). Thorough: report() keeps under context.WithoutCancel with a 5 s bound; the same test now passes 40 of 40.

Claude-Session: https://claude.ai/code/session_01JG73KG7AfSdh6FP8VrBqCn

modules/mesh-provisioner-client/cmd/mesh-provisioner-client/client.go

@@ -970,7 +970,11 @@ func (c *Client) report(ctx context.Context, kvs map[string]jetstream.KeyValue,
 		logf("[provisioner-client] the report of %s: %v", r.Module, err)
 		return
 	}
-	if _, err := kvs[AppliedBucket].Put(ctx, c.Node+"."+r.Module, body); err != nil {
+	// Kept under a context the client's stop does not cancel, bounded: a report made as the client stops is still kept,
+	// or s.applied would never name the module and a later pass would never remove it (leftModules).
+	keep, done := context.WithTimeout(context.WithoutCancel(ctx), 5*time.Second)
+	defer done()
+	if _, err := kvs[AppliedBucket].Put(keep, c.Node+"."+r.Module, body); err != nil {
 		logf("[provisioner-client] the report of %s could not be kept: %v", r.Module, err)
 	} else {
 		s.applied[r.Module] = true