feat(web): tell the user when a video track was ignored, in every state

A Teams meeting with the camera off is still a video file. It is accepted, only
its audio is transcribed, and the page says so in queued, transcribing, done and
failed -- not just at the end.

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

internal/web/uploads.templ

@@ -60,6 +60,7 @@ templ uploadStatus(u domain.UploadedTranscript, chatEnabled bool) {
 	switch u.Status {
 		case domain.UploadDone:
 			<div class="upload-status upload-done" role="status">
+				@videoNotice(u.HadVideo)
 				<p>
 					Transcribed { uploads.FormatDuration(time.Duration(u.AudioSeconds * float64(time.Second))) }
 					of audio by <span class="chip">{ u.Endpoint }</span>.
@@ -74,6 +75,7 @@ templ uploadStatus(u domain.UploadedTranscript, chatEnabled bool) {
 			</div>
 		case domain.UploadFailed:
 			<div class="upload-status upload-failed flash flash-error" role="alert">
+				@videoNotice(u.HadVideo)
 				<p>{ uploadFailureMessage(u.ErrorKind) }</p>
 			</div>
 		default:
@@ -84,6 +86,7 @@ templ uploadStatus(u domain.UploadedTranscript, chatEnabled bool) {
 				hx-trigger={ "every " + uploadPollEvery }
 				hx-swap="outerHTML"
 			>
+				@videoNotice(u.HadVideo)
 				if u.Status == domain.UploadTranscribing {
 					<p>Transcribing… a long recording takes a few minutes.</p>
 				} else {
@@ -108,3 +111,15 @@ templ UploadChatPage(u domain.UploadedTranscript, v chatView) {
 		</article>
 	}
 }
+
+// videoNotice tells the user a video track was present and what became of it. A
+// Teams meeting with the camera off is still a video file; it is accepted, only the
+// audio is transcribed, and the picture is thrown away — so say so, in every state,
+// instead of leaving the user to wonder (ADR-033).
+templ videoNotice(hadVideo bool) {
+	if hadVideo {
+		<p class="muted video-notice">
+			This file contained a video track. Only its audio was used; the video was discarded and nothing from it was kept.
+		</p>
+	}
+}