my-sea deck-stack + spread-card glow: unify hover-reveal / click-persist + --ninUser halo — TDD

Unify the glow/FLIP interaction across the owner picker (my_sea) + the read-only
spectator (my_sea_visit), then carry the same selection halo onto the spread
cards + deck-stack faces.

DECK STACK (user-spec 2026-05-30) — the owner revealed the FLIP only on click
(persisted) but never on hover; the spectator revealed it on hover but never
persisted. Now BOTH do both:
- `.sea-stack-ok` reveal is a single shared rule in _card-deck.scss — opacity
  fades in on hover/focus (ephemeral) OR via the JS-set `.sea-deck-stack--active`
  class (click-persist, same class the face-glow rides). The owner's inline
  `display` toggling is gone (`_showOk`/`_hideOk` just flip `--active`); the
  spectator's hover-only override in _gameboard.scss is removed.
- Interactivity stays gated on `--active`, NOT hover: hover is a purely VISUAL
  preview (matching the spectator's disabled FLIP). This preserves the owner's
  two-step deal — were the FLIP click-through on hover, a single stack-click
  would land on the centred FLIP + deal early (caught by the draw FT).
- Spectator persist wired in my_sea_visit.html (click a stack → `--active`,
  click elsewhere clears); its FLIP stays `.btn-disabled` (read-only).

SPREAD CARDS — the same hover-glow + active-persist now on EVERY spread card,
building on the cover/cross rules. The prior `.sea-card-slot--focused` glow
(0-1-0) was silently overridden by the filled-card drop-shadow ladder (up to
0-4-0) and never rendered (verified live); `!important` (consistent w. the
existing `opacity:1 !important` there) makes the halo win on hover + focus. The
halo is symmetric (rotation-invariant). No colour change — box-shadow only.

DECK FACE HALO — the levity + gravity stack glows now mirror the card halo's
tuned geometry (0.5rem blur / 0.5rem spread / 0.3 alpha), each in its own
polarity colour (--ninUser / --quaUser); single keeps its own tone.

Verified live in Firefox: deck FLIP persists on click + fades on hover; the card
halo wins over the drop-shadow on hover/focus across crown/cover/(reversed-)cross;
levity/gravity deck glows match the card halo. Draw FTs green (single-draw, hand-
completion, AUTO DRAW, auto-drawn-slot reopen) — the two-step deal + card focus
survive the display→opacity switch.

Code architected by Disco DeDisco <discodedisco@outlook.com>
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/static_src/scss/_gameboard.scss

@@ -808,20 +808,11 @@ body.page-gameboard {
         transform-origin: center;
     }
 
-    // Read-only FLIP (disabled ×) — hidden until its stack is hovered/focused,
-    // then eases in: same reveal shape as the shared `flip-btn-base` mixin
-    // (opacity 0→1 over 0.3s ease), inlined here because _gameboard.scss is
-    // imported before _card-deck.scss (where the mixin lives). Stays non-
-    // interactive — `.btn-disabled` keeps pointer-events:none. The base
-    // `.sea-stack-ok` positioning is untouched (we only add the fade).
-    .sea-stack-ok {
-        opacity: 0;
-        transition: opacity 0.3s ease;
-    }
-    .sea-deck-stack:hover .sea-stack-ok,
-    .sea-deck-stack:focus-within .sea-stack-ok {
-        opacity: 1;
-    }
+    // FLIP reveal (hover-fade + click-persist) is now the SHARED `.sea-stack-ok`
+    // behaviour in _card-deck.scss — unified with the owner picker per user-spec
+    // 2026-05-30, so the visitor's prior hover-only override is gone. The
+    // spectator's click-persist (`.sea-deck-stack--active`) is wired in
+    // my_sea_visit.html (the read-only FLIP stays disabled throughout).
 }
 
 // ── Iter 4b: Brief banner + DEL guard portal ─────────────────────────────────