Make no value for an own secret issued outside the mesh that nobody gave (issue 401)

The send minted a random value for a plain own secret marked issued-by outside and placed it, so a
module could not tell "not given" from "given and wrong" (ADR 0228). It now places only a value a
person gave: not given is no file, an empty value where a module's file names it, and nothing to
restart on, as ADR 0283 decided for a family's member. A value the mesh made for one earlier is not
read as given.

internal/catalogue/secrets_into_files.go

@@ -156,7 +156,11 @@ func secretFilesOf(resources []map[string]any) map[string]bool {
 // A name the module never declared is refused here rather than on the machine. The host would
 // refuse it too — but it would do so having already been handed a declaration, which reads as the
 // mesh sending something broken, and the name it could not find is a manifest's typo.
-func intoFile(resource map[string]any, sealed map[string]string, module string) error {
+//
+// **An own secret issued outside the mesh that nobody gave is filled with nothing** (novox/hq issue 401): the mesh
+// never makes one (ADR 0228), and a file is where the module reads it, so the place says empty — the module sees it
+// was not given, where a value the mesh made looked given and wrong. notGiven names those secrets.
+func intoFile(resource map[string]any, sealed map[string]string, notGiven map[string]bool, module string) error {
 	if fmt.Sprint(resource["type"]) != "file" {
 		return nil
 	}
@@ -171,6 +175,10 @@ func intoFile(resource map[string]any, sealed map[string]string, module string)
 	into := map[string]any{}
 	for _, name := range used {
 		value := sealed[name]
+		if value == "" && notGiven[name] {
+			content = strings.ReplaceAll(content, "${secret:"+name+"}", "")
+			continue
+		}
 		if value == "" {
 			return fmt.Errorf(
 				"%s has a file that says ${secret:%s}, and %s has no secret of its own by that "+
@@ -179,10 +187,25 @@ func intoFile(resource map[string]any, sealed map[string]string, module string)
 		}
 		into[name] = value
 	}
-	resource["secrets"] = into
+	resource["content"] = content
+	if len(into) > 0 {
+		resource["secrets"] = into
+	}
 	return nil
 }
 
+// outsideNotGiven is each own secret of a module issued outside the mesh that this composition holds no value for
+// (novox/hq issue 401): what intoFile fills with nothing, and what nothing restarts on.
+func outsideNotGiven(m Manifest, given map[string]string) map[string]bool {
+	out := map[string]bool{}
+	for name, own := range m.OwnSecrets.Plain() {
+		if own.IssuedBy == IssuedOutside && given[name] == "" {
+			out[name] = true
+		}
+	}
+	return out
+}
+
 // namesOr says what a module could have written, because the answer to "that name is wrong" is
 // almost always one of two or three right ones.
 func namesOr(sealed map[string]string) string {