M6.16: Unified hybrid species grid + codex-styled hover popover

StepSpecies hybrid mode now uses one grid combining sire-clade species
(under a "SIRE — <Clade>" eyebrow) and dam-clade species (under
"DAM — <Clade>"). Cards are click-to-select like the purebred path —
since clades are guaranteed disjoint by StepClade's parent-conflict
rule, the lineage is implicit from the species' clade and no per-card
toggles are needed.

Hover popover now picks up the codex theme: parchment Bg2 panel with a
gild border, rounded 14px corners, and soft drop shadow; H3 display
serif title, mono Eyebrow tag, CardBody description. Detriment popovers
swap to a 3px seal-red border via the panel_detriment stylebox override
(replaces the old red Modulate hack).

Theme propagation fix: CanvasLayer breaks Godot's Control theme
inheritance, so the popup was rendering on Godot defaults. _Ready
defers a lookup of the parent Control's theme and assigns it directly
to the popup so the codex parchment + Cormorant/CrimsonPro fonts
actually resolve.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Theriapolis.Godot/Scenes/Steps/StepSpecies.cs

@@ -7,9 +7,11 @@ namespace Theriapolis.GodotHost.Scenes.Steps;
 
 /// <summary>
 /// Step II — Species. Direct port of <c>StepSpecies</c> in
-/// <c>src/steps.jsx</c> plus the Phase 6.5 hybrid extension: when
-/// <see cref="CharacterDraft.IsHybrid"/> is true the step shows two
-/// stacked grids, one filtered by SireCladeId and one by DamCladeId.
+/// <c>src/steps.jsx</c> plus the Phase 6.5 hybrid extension. Hybrid mode
+/// uses a single unified grid (M6.16) — sire and dam species lists are
+/// merged, and each card carries either a Sire or Dam toggle in its
+/// header matching the clade it belongs to (sire/dam clades are
+/// guaranteed disjoint by StepClade's parent-conflict rule).
 /// </summary>
 public partial class StepSpecies : VBoxContainer, IStep
 {
@@ -17,8 +19,7 @@ public partial class StepSpecies : VBoxContainer, IStep
     private VBoxContainer _purebredSection = null!;
     private VBoxContainer _hybridSection = null!;
     private GridContainer _purebredGrid = null!;
-    private GridContainer _sireGrid = null!;
-    private GridContainer _damGrid = null!;
+    private GridContainer _hybridGrid = null!;
 
     // Phase B species trait + detriment pickers — single-pick per lineage.
     private VBoxContainer _pickSection = null!;
@@ -77,13 +78,14 @@ public partial class StepSpecies : VBoxContainer, IStep
         _hybridSection.AddThemeConstantOverride("separation", 16);
         AddChild(_hybridSection);
 
-        _hybridSection.AddChild(new Label { Text = "SIRE — Paternal Lineage", ThemeTypeVariation = "Eyebrow" });
-        _sireGrid = MakeGrid();
-        _hybridSection.AddChild(_sireGrid);
-
-        _hybridSection.AddChild(new Label { Text = "DAM — Maternal Lineage", ThemeTypeVariation = "Eyebrow" });
-        _damGrid = MakeGrid();
-        _hybridSection.AddChild(_damGrid);
+        _hybridSection.AddChild(new Label
+        {
+            Text = "Pick one species per parent lineage. Sire's clade species "
+                 + "are listed first, then Dam's — click any card to pick it.",
+            AutowrapMode = TextServer.AutowrapMode.WordSmart,
+        });
+        _hybridGrid = MakeGrid();
+        _hybridSection.AddChild(_hybridGrid);
 
         // Phase B species pickers: one trait + one detriment per parent.
         _pickSection = new VBoxContainer();
@@ -130,10 +132,7 @@ public partial class StepSpecies : VBoxContainer, IStep
 
         if (hybrid)
         {
-            RefreshGrid(_sireGrid, _draft.SireCladeId, _draft.SireSpeciesId,
-                spId => OnLineageSpeciesPicked("sire", spId));
-            RefreshGrid(_damGrid, _draft.DamCladeId, _draft.DamSpeciesId,
-                spId => OnLineageSpeciesPicked("dam", spId));
+            RefreshHybridGrid();
 
             SyncSpeciesPicks(_sirePickCol, ref _sirePicksBuiltFor, "sire",
                 _draft.SireSpeciesId, _draft.SireChosenSpeciesTrait, _draft.SireChosenSpeciesDetriment);
@@ -398,6 +397,35 @@ public partial class StepSpecies : VBoxContainer, IStep
             grid.AddChild(BuildCard(sp, sp.Id == selectedSpecies, onClick));
     }
 
+    /// <summary>
+    /// Hybrid mode: rebuild the unified grid with sire-clade species
+    /// followed by dam-clade species. Sire and dam clades are
+    /// guaranteed distinct by StepClade's parent-conflict rule, so the
+    /// species lists are disjoint — each card unambiguously belongs to
+    /// one lineage and a click on the card commits the pick. Full
+    /// rebuild on every Refresh is safe because Bind installs Refresh
+    /// as a deferred callback.
+    /// </summary>
+    private void RefreshHybridGrid()
+    {
+        foreach (var c in _hybridGrid.GetChildren()) c.Free();
+        AddHybridLineageBlock("sire", _draft.SireCladeId, _draft.SireSpeciesId);
+        AddHybridLineageBlock("dam",  _draft.DamCladeId,  _draft.DamSpeciesId);
+    }
+
+    private void AddHybridLineageBlock(string lineage, string cladeId, string selectedSpeciesId)
+    {
+        if (string.IsNullOrEmpty(cladeId)) return;
+        var clade = CodexContent.Clade(cladeId);
+        string headerLabel = (lineage == "sire" ? "SIRE" : "DAM")
+            + (clade is null ? "" : " — " + clade.Name.ToUpperInvariant());
+        _hybridGrid.AddChild(new Label { Text = headerLabel, ThemeTypeVariation = "Eyebrow" });
+
+        foreach (var sp in CodexContent.SpeciesOfClade(cladeId))
+            _hybridGrid.AddChild(BuildCard(sp, sp.Id == selectedSpeciesId,
+                spId => OnLineageSpeciesPicked(lineage, spId)));
+    }
+
     private static Control BuildCard(SpeciesDef sp, bool selected, System.Action<string> onClick)
     {
         var card = CodexCard.Make();