style: apply gofmt

Estate-wide consolidation pass. golangci-lint v2 default set enables NO
formatter, so gofmt drift accumulated silently across the estate -- 8 repos
were carrying it, this one included. Same hole that let two files rot in
dma-cli until they were found by hand (dma-cli#12).

Mechanical and deterministic: `gofmt -w`, nothing hand-edited. Verified
before commit -- gofmt -l now reports 0, go build and go vet both pass.

Clears this repo to adopt the canonical .golangci.yml (infra
ci-templates/golangci.yml, infra#309 pattern) in a later wave.

internal/session/history_test.go

@@ -20,8 +20,8 @@ func TestFormatHistoryFormatsEntries(t *testing.T) {
 	entries := []session.Entry{
 		{
 			Skill: "tdd", Phase: "red", FinalStatus: "pass",
-			FilePath: "internal/foo/foo_test.go",
-			Message:  "wrote failing test for Foo",
+			FilePath:  "internal/foo/foo_test.go",
+			Message:   "wrote failing test for Foo",
 			Timestamp: time.Now(),
 		},
 	}