feat(master): circular token style with pink/green ring per value range

Replaces the orange/red filled-square cells on the master tracking
board with a circular token treatment inspired by the Hội chợ "Các
số đã ra" panel. Each numbered cell now renders a centered circle
with a colored ring — pink for 1–49, green for 50–90 — over a
cream-yellow fill when the number has been called, or dimmed/empty
when it has not. The most recent draw keeps its red accent via a
ring-offset highlight + slight scale, so the host can still find
"vừa xổ" at a glance. Draw-order superscript stays at the cell's
top-right corner, now in muted slate (visible against both the
cream-filled and dim-empty token states).

web/docs/codebase-summary.md

@@ -7,7 +7,7 @@
 |------|---------|
 | `src/routes/+layout.svelte` | Root HTML layout. Sets Vietnamese lang, imports Geist font, applies global flex layout. |
 | `src/routes/+page.svelte` | Player page (`/`). Instructions toggle, PlayerBoard component, indigo gradient branding. |
-| `src/routes/master/+page.svelte` | Host page (`/master`). Controls (new game, draw number), 11×9 last-digit-aligned master board with draw-order overlay, host's player card. |
+| `src/routes/master/+page.svelte` | Host page (`/master`). Controls (new game, draw number), 11×9 last-digit-aligned master board with circular tokens (pink ring for 1–49, green for 50–90; cream fill when called, dim when uncalled; red ring + scale on last-called) and draw-order overlay, host's player card. |
 
 ### Shared Components
 | File | Purpose |

web/docs/project-overview-pdr.md

@@ -26,7 +26,9 @@ That format is intentionally out of scope.
   may keep playing further rows (game does not end).
 - **Waiting state**: when a row needs only 1 number, app announces **"Chờ N"**.
 - **Host (quản trò)** draws numbers from a shuffled 1–90 deck, tracks them on
-  a master board, and may also play their own card.
+  a master board with circular tokens (pink ring for 1–49, green for 50–90,
+  cream fill on called, dim on uncalled, red ring + scale on the most
+  recent draw), and may also play their own card.
 - **Settings**: gear icon in headers opens a modal with a color picker for
   the empty/blank cell color (default brown matches physical card).
   Persisted to `loto_settings`.