feat(dolt): auto-commit write commands and set explicit commit authors (#1270)

Adds Dolt auto-commit functionality for write commands and sets explicit commit authors.

Includes fix for race condition in commandDidWrite (converted to atomic.Bool).

Original PR: #1267 by @coffeegoddd
Co-authored-by: Dustin Brown <dustin@dolthub.com>

cmd/bd/dolt_autocommit_config.go

@@ -0,0 +1,28 @@
+package main
+
+import (
+	"fmt"
+	"strings"
+)
+
+type doltAutoCommitMode string
+
+const (
+	doltAutoCommitOff doltAutoCommitMode = "off"
+	doltAutoCommitOn  doltAutoCommitMode = "on"
+)
+
+func getDoltAutoCommitMode() (doltAutoCommitMode, error) {
+	mode := strings.TrimSpace(strings.ToLower(doltAutoCommit))
+	if mode == "" {
+		mode = string(doltAutoCommitOn)
+	}
+	switch doltAutoCommitMode(mode) {
+	case doltAutoCommitOff:
+		return doltAutoCommitOff, nil
+	case doltAutoCommitOn:
+		return doltAutoCommitOn, nil
+	default:
+		return "", fmt.Errorf("invalid --dolt-auto-commit=%q (valid: off, on)", doltAutoCommit)
+	}
+}