fix: MSSQLSERVER dual-entry bug, README batch script, and test DB dependency

- Remove duplicate (local) entry for default MSSQLSERVER instance
- Fix README batch script: %%~z outside FOR loop doesn't work, use FOR %%I
- TestHelpCommand/TestServerlistCommand no longer require DB connection

Author: dlevy-msft-sql

README.md

@@ -205,7 +205,7 @@ echo No SQL Server instances found
 To capture stderr separately (for error logging):
 ```batch
 sqlcmd -Q ":serverlist" 2>errors.log > servers.txt
-if exist errors.log if not "%%~z errors.log"=="0" type errors.log
+if exist errors.log for %%I in (errors.log) do if %%~zI gtr 0 type errors.log
 ```
 
 ```

pkg/sqlcmd/commands_test.go

@@ -470,9 +470,11 @@ func TestExitCommandAppendsParameterToCurrentBatch(t *testing.T) {
 }
 
 func TestHelpCommand(t *testing.T) {
-	s, buf := setupSqlCmdWithMemoryOutput(t)
-	defer func() { _ = buf.Close() }()
+	v := InitializeVariables(false)
+	s := New(nil, "", v)
+	buf := &memoryBuffer{buf: new(bytes.Buffer)}
 	s.SetOutput(buf)
+	defer func() { _ = buf.Close() }()
 
 	err := helpCommand(s, []string{""}, 1)
 	assert.NoError(t, err, "helpCommand should not error")

pkg/sqlcmd/serverlist.go

@@ -80,7 +80,7 @@ func GetLocalServerInstances() ([]string, error) {
 			continue
 		}
 		if s == "MSSQLSERVER" {
-			instances = append(instances, "(local)", serverName)
+			instances = append(instances, serverName)
 		} else {
 			instances = append(instances, fmt.Sprintf(`%s\%s`, serverName, s))
 		}

pkg/sqlcmd/serverlist_test.go

@@ -76,12 +76,14 @@ func TestParseInstances(t *testing.T) {
 }
 
 func TestServerlistCommand(t *testing.T) {
-	s, buf := setupSqlCmdWithMemoryOutput(t)
+	v := InitializeVariables(false)
+	s := New(nil, "", v)
+	buf := &memoryBuffer{buf: new(bytes.Buffer)}
+	s.SetOutput(buf)
 	defer func() { _ = buf.Close() }()
 
-	// Run the serverlist command
-	c := []string{":serverlist"}
-	err := runSqlCmd(t, s, c)
+	// Run the serverlist command directly - no DB connection needed
+	err := serverlistCommand(s, []string{""}, 1)
 
 	// The command should not raise an error even if no servers are found
 	assert.NoError(t, err, ":serverlist should not raise error")