PICK SEA reversal axis: server-side roll + preview + deposited slot — TDD

- new apps/epic/utils.STACK_REVERSAL_PROBABILITY (=0.25) + stack_reversal_probability(user, room) helper; single source of truth across game phases & one-line swap point for forthcoming per-user-profile config
- sea_deck view rolls each card's `reversed` axis at fetch time using the helper, attaches to card JSON; matches the eager shuffle pattern (whole deal determined at phase start)
- room_view + sea_partial pass `stack_reversal_pct` into context for the new <p class="sea-reversal-hint">25% reversals</p> hint above the SPREAD combobox (italic, 0.7rem, 0.55 opacity)
- SeaDeal.openStage applies .stage-card--reversed + .is-reversed to stat block when card.reversed → preview lands face-reversed w. REVERSAL keywords
- _fillSlot adds .sea-card-slot--reversed → slot itself rotates 180° (bg + border + content stack flips, not just inner chars upside-down in place); .sea-pos-cross overrides to 270° to compose w. its existing 90°
- _fillSlot adds .sea-card-slot--rank-long when corner_rank.length ≥ 5 (XVIII / XXIII / XXVIII / XXXIII / XXXVIII / XLIII / XLVIII) → SCSS scaleX(0.7) + letter-spacing -0.05em squeezes horizontally w.o changing font-size

Code architected by Disco DeDisco <discodedisco@outlook.com>
Git commit message Co-Authored-By:
Claude Sonnet 4.6 <noreply@anthropic.com>

src/templates/apps/gameboard/_partials/_sea_overlay.html

@@ -13,7 +13,7 @@
 
         <header class="sea-modal-header">
             <h2>PICK <span>SEA</span></h2>
-            <p>Draw cards to circumscribe your character's influences and seed the Voronoi map.</p>
+            <p>Draw +6 cards to describe your character's influences and seed the game-map.</p>
         </header>
 
         <div class="sea-modal-body">
@@ -63,6 +63,13 @@
                 <div class="sea-form-main">
                     <div class="sea-field">
                         <label for="id_sea_spread" id="id_sea_spread_label">Spread</label>
+                        {% comment %}
+                            Reversal-rate hint — `stack_reversal_pct` flows from
+                            apps.epic.utils.stack_reversal_probability via the
+                            view. Currently a module default; placeholder UI for
+                            a forthcoming per-user setting.
+                        {% endcomment %}
+                        <p class="sea-reversal-hint">{{ stack_reversal_pct|default:25 }}% reversals</p>
                         {% comment %}
                             Custom combobox — native <select> dropdowns ignore most CSS on
                             Firefox/Chrome (OS-rendered list); this gives full styling control.