gofmt: bring internal/ and cmd/ back to gofmt -l clean

Mechanical `gofmt -w ./internal ./cmd`. Mostly struct-field realignment that
had drifted, plus a few trailing-newline fixes. No behaviour change — gofmt is
semantics-preserving, and build/vet/test are green either side.

Split out from the code-review fixes that follow so those stay reviewable
instead of hiding inside a wall of realignment.

internal/util/parser.go

@@ -10,13 +10,13 @@ import (
 
 // MessageStats holds parsed message metrics.
 type MessageStats struct {
-	Words       int
-	Chars       int
-	Links       int
-	Images      int
-	Questions   int
+	Words        int
+	Chars        int
+	Links        int
+	Images       int
+	Questions    int
 	Exclamations int
-	Emojis      int
+	Emojis       int
 }
 
 var (