feat(uploads): choose the language of a recording; record it, show it, carry it to the engines (#61)

Form field (Swedish preselected, Other = auto) read before the file part and refused
before anything is spooled if outside the closed set; stored on the row (migration 021,
CHECK constraint, default sv for history); carried on the Job and the worker's context;
shown on the status page. Feature scenarios and the coverage map are updated, and
ADR-033/034 amended.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

internal/web/uploads_handler_test.go

@@ -16,6 +16,7 @@ import (
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 
+	"git.d-ma.be/mathias/tapir/internal/domain"
 	"git.d-ma.be/mathias/tapir/internal/uploads"
 	"git.d-ma.be/mathias/tapir/internal/web"
 )
@@ -132,7 +133,7 @@ func TestUploadPost_AcceptedAudioQueuesARowAndRedirectsToIt(t *testing.T) {
 	assert.Equal(t, "Sprint review", title)
 	assert.Equal(t, "/uploads/"+id, rec.Header().Get("Location"))
 	require.Len(t, sub.jobs, 1)
-	assert.Equal(t, uploads.Job{UserID: userID, UploadID: id, Path: sub.jobs[0].Path, Duration: audioOK.Duration}, sub.jobs[0])
+	assert.Equal(t, uploads.Job{UserID: userID, UploadID: id, Path: sub.jobs[0].Path, Language: domain.LangSwedish, Duration: audioOK.Duration}, sub.jobs[0])
 	spooled, err := os.ReadFile(sub.jobs[0].Path)
 	require.NoError(t, err)
 	assert.Equal(t, "synthetic audio bytes", string(spooled))