Show BPM (left) and track length (right) at 2x, above the progress bar

New track_length ("M:SS" from duration) and bpm ("N bpm", rounded)
formatted fields on the now-playing fetch. 2x only, tied to the
progress bar's own presence (both come from data that's only
meaningful on a long-lived server -- see _track_progress's own
comment), since the row is meant to sit directly above it rather than
float with nothing below it.

Right-aligns track_length via a computed left Padding/spacer Box (same
estimated-width approach already used for time_temp's centering), not
render.Row(expanded=True, main_align="space_between") -- that pattern
already caused a real bug once this session (the time_temp centering
fix): `expanded` on a Row grabs extra *vertical* space from the
enclosing Column (main_align="space_between"), pushing the progress
bar out of view. Caught this before it shipped by pixel-sampling the
bottom rows and confirming the progress bar's exact "bar_empty" color
is still present where expected, not just eyeballing the render.

Verified: renders between time_temp and the progress bar at 2x ("136
bpm" / "6:45"), 1x unaffected (no new row, unchanged layout).

subwave_nowplaying.star

@@ -356,6 +356,34 @@ def main(config):
     ] + show_lines + [time_temp_line]
 
     children = [render.Column(children = top_lines)]
+
+    # BPM (left) / track length (right), 2x only -- same reasoning as the
+    # other 2x-only additions above: no spare row for it at 1x's tighter
+    # layout. Tied to the progress bar's own presence (both come from
+    # _track_progress/duration data that's only meaningful on a
+    # long-lived server, not a one-shot CLI render -- see _track_progress's
+    # own comment), since it's meant to sit directly above it, not float
+    # on its own if there's nothing below it.
+    #
+    # Right-aligns track_length via a computed left Padding (same
+    # estimated-width approach as time_temp's centering), not
+    # render.Row(expanded=True, main_align="space_between") -- that
+    # pattern already caused a real bug once this session (the
+    # time_temp centering fix): `expanded` on a Row grabs extra
+    # *vertical* space from this same enclosing Column
+    # (main_align="space_between"), which pushed the progress bar below
+    # it out of view. A plain Row with a computed Box spacer between the
+    # two texts can't do that, since nothing in it is flexible/expanding.
+    if scale == 2 and progress != None:
+        bpm_width = int(len(list(now["bpm"].codepoints())) * 3.9)
+        length_width = int(len(list(now["track_length"].codepoints())) * 3.9)
+        gap = max(0, text_width - bpm_width - length_width)
+        children.append(render.Row(children = [
+            render.Text(now["bpm"], font = "tom-thumb", color = colors["meta"]),
+            render.Box(width = gap, height = 1),
+            render.Text(now["track_length"], font = "tom-thumb", color = colors["meta"]),
+        ]))
+
     if progress != None:
         children.append(_progress_bar(progress["fraction"], colors, width = text_width, height = 2 * scale))
 
@@ -1002,6 +1030,8 @@ def _fetch_now_playing(station_url):
         "host": dj.get("name", ""),
         "time_temp": _format_time_temp(context.get("clock", {}) or {}, context.get("weather", {}) or {}),
         "album_year": _format_album_year(np.get("album", ""), np.get("year", None)),
+        "track_length": _format_track_length(np.get("duration", 0)),
+        "bpm": _format_bpm(np.get("bpm", None)),
         "online": bool(data.get("streamOnline", False)),
     }
 
@@ -1013,6 +1043,20 @@ def _format_album_year(album, year):
         parts.append(str(int(year)))
     return " · ".join(parts)
 
+def _format_track_length(duration):
+    if not duration:
+        return ""
+    total = int(duration)
+    minutes = total // 60
+    seconds = total % 60
+    secs_str = "0" + str(seconds) if seconds < 10 else str(seconds)
+    return str(minutes) + ":" + secs_str
+
+def _format_bpm(bpm):
+    if not bpm:
+        return ""
+    return str(int(bpm + 0.5)) + " bpm"
+
 def _format_time_temp(clock, weather):
     parts = []
     display_time = clock.get("display", "")