feat(dolt): auto-commit write commands and set explicit commit authors (#1267)

* /{cmd,docs,internal}: autocommit writes in dolt backend

Executed-By: beads/crew/emma
Rig: beads
Role: crew

* /{cmd,internal}: fix commit author

Executed-By: beads/crew/emma
Rig: beads
Role: crew

* /cmd/bd: fix race condition

Executed-By: beads/crew/emma
Rig: beads
Role: crew

---------

Co-authored-by: Test <test@example.com>

cmd/bd/sync_import.go

@@ -136,14 +136,7 @@ func importFromJSONLInline(ctx context.Context, jsonlPath string, renameOnImport
 		return fmt.Errorf("import failed: %w", err)
 	}
 
-	// Mark command as having performed a write when the import changed anything.
-	// This enables Dolt auto-commit in PersistentPostRun.
-	if result.Created > 0 || result.Updated > 0 || len(result.IDMapping) > 0 {
-		commandDidWrite.Store(true)
-	}
-
-	// Mark command as having performed a write when the import changed anything.
-	// This enables Dolt auto-commit in PersistentPostRun for single-process backends.
+	// Record that this command performed a write (for Dolt auto-commit) when the import changed anything.
 	if result.Created > 0 || result.Updated > 0 || len(result.IDMapping) > 0 {
 		commandDidWrite.Store(true)
 	}