Publish a module's ledger history and snapshots only on its own ledger connection, read from the runner's own secret ledgers and followed without a restart (issue 1966 T6)

node-tools/internal/bus/bus.go

@@ -288,9 +288,20 @@ func (c *Conn) refused(err error) {
 	})
 }
 
-// Connect dials the bus as the credential's module. A module's subjects come from its credential,
-// never from its calls (ADR 0074).
+// Connect dials the bus as the credential's module and follows its membership. A module's subjects come from its
+// credential, never from its calls (ADR 0074).
 func Connect(cred Credential) (*Conn, error) {
+	c, err := Dial(cred)
+	if err != nil {
+		return nil, err
+	}
+	c.Follow(cred.Module)
+	return c, nil
+}
+
+// Dial dials the bus as the credential's module and follows nothing: a connection that only publishes for its module,
+// as a module's ledger connection does (novox/hq ADR 0597 §9).
+func Dial(cred Credential) (*Conn, error) {
 	if cred.Module == "" {
 		return nil, errors.New("a broker credential with no module: the runtime derives its subjects " +
 			"from the account the mesh issued, and cannot guess which module it is")
@@ -329,7 +340,6 @@ func Connect(cred Credential) (*Conn, error) {
 	}
 	c = &Conn{nc: nc, js: js, self: cred.Module, node: cred.Node, cred: cred,
 		issued: map[string]*Membership{}, Logf: log.Printf, answering: map[string]*answered{}}
-	c.Follow(cred.Module)
 	return c, nil
 }