Calendar mode polish batch + Today & Tomorrow view

Responds to post-launch feedback on calendar mode: configurable
week-start day for week/month views, crisper non-antialiased text
(threshold-masked instead of drawn straight, so Floyd-Steinberg
dithering doesn't speckle glyph edges), a color-coded/proportionally
filled battery icon on the manage overlay, word-wrapped placeholder
text so "Calendar isn't set up yet" no longer clips in portrait, photo
inlay support extended from agenda-only to every view, and a fix so
manage-overlay face labels reposition correctly when a photo inlay is
active (they previously assumed the photo filled the whole canvas).

Also adds a fourth calendar view, "Today & Tomorrow" -- a two-day
agenda that reuses the same per-day row-layout helper the single-day
agenda view already has.

server/app/routers/api_frames.py

@@ -99,6 +99,7 @@ def api_config_save(
     mode: str | None = Form(None),
     calendar_view: str | None = Form(None),
     calendar_photo_inlay: bool | None = Form(None),
+    calendar_week_start: int | None = Form(None),
     frame: Frame = Depends(require_frame_control),
     db: Session = Depends(get_db),
 ):
@@ -174,6 +175,8 @@ def api_config_save(
             cfg.calendar_view = new_view
         if calendar_photo_inlay is not None:
             cfg.calendar_photo_inlay = calendar_photo_inlay
+        if calendar_week_start is not None:
+            cfg.calendar_week_start = max(0, min(6, calendar_week_start))
         cfg.stats_config_saves += 1
     return {"status": "saved"}
 
@@ -436,13 +439,13 @@ def api_calendar_included(
 
 
 def _calendar_photo_inlay(frame: Frame, db: Session):
-    """The agenda view's optional photo-inlay source image, or None if
-    inlay is off, not agenda view, or the frame's photos-mode album isn't
+    """The photo-inlay's source image (any view now, not just agenda), or
+    None if inlay is off or the frame's photos-mode album isn't
     configured. Shared shape between the live render (routers/device.py's
     _render_calendar_mode) and this preview endpoint; small enough that
     duplicating rather than factoring out is fine, since the two call
     sites differ slightly in error handling."""
-    if not (frame.calendar_view == "agenda" and frame.calendar_photo_inlay):
+    if not frame.calendar_photo_inlay:
         return None
     url, key = immich_creds(frame)
     if not (url and key and frame.album_id):
@@ -477,6 +480,7 @@ def api_preview_calendar(frame: Frame = Depends(require_frame_view), db: Session
     png = calendar_render.render_calendar_preview_png(
         events, view=view, browse_offset=frame.calendar_browse_offset, orientation=frame.orientation,
         palette_rgb=frame.palette_rgb, timezone=frame.timezone, photo_inlay=photo_inlay, fetch_summary=summary,
+        week_start=frame.calendar_week_start,
     )
     return Response(content=png, media_type="image/png")