$WOW_CAPTURE_SPELLS: seat a real spellbook in a capture

A capture never logs in, so its spellbook is whatever a fixture hardcodes — and a whole class of
addon is driven by what is IN that book. Advanced Trade Skill Window finds the player's
professions by walking spell tab 1 and matching each spell's icon against its own thirteen
`Interface\Icons\…` leaves, so with no profession spell seated it finds nothing, draws no tab and
switches nothing: indistinguishable from the defect being chased.

With it, grom's report reproduces offline. The realm's own ids are in the comment — Survival is
**46050**, a profession 1.12 does not have and the one his screenshot is of — and seating
46050,2550,3273,2018,2656 builds five named, shown, correctly-icon'd tabs, which is how the icon
match was cleared as the cause of *"I can't switch to other professions."*

Added to the fixture's own book rather than replacing it, so every existing scenario still reads
as it did.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01SgstFWtn1RxEJ5kVrpgYwn

crates/benilla-app/src/capture/fixtures.rs

@@ -124,6 +124,32 @@ pub(super) fn seed_ui_fixture(
     }
     ctx.ui_seeded = true;
 
+    // `$WOW_CAPTURE_SPELLS=<id>[,<id>…]`: spells added to whatever book the fixture seats.
+    //
+    // A capture never logs in, so its spellbook is whatever a fixture hardcodes — and a whole
+    // class of addon is driven by what is IN that book. Advanced Trade Skill Window finds the
+    // player's professions by walking tab 1 and matching each spell's icon against its own list
+    // (`Professions`, thirteen `Interface\Icons\…` leaves), so with no profession spell seated
+    // it finds nothing, draws no tab and switches nothing — which is indistinguishable from the
+    // defect being chased. The realm's own ids: Survival 46050, Jewelcrafting 30220, and 1.12's
+    // own Alchemy 2259, Blacksmithing 2018, Cooking 2550, Enchanting 7411, Engineering 4036,
+    // First Aid 3273, Leatherworking 2108, Tailoring 3908, Smelting 2656.
+    //
+    // Added rather than replacing, so a scenario's own book still reads as it did.
+    if let Ok(list) = std::env::var("WOW_CAPTURE_SPELLS") {
+        let extra: Vec<u32> = list
+            .split(',')
+            .filter_map(|s| s.trim().parse().ok())
+            .collect();
+        if !extra.is_empty() {
+            info!(
+                "capture: $WOW_CAPTURE_SPELLS seats {} extra spell(s)",
+                extra.len()
+            );
+            actions.spells.extend(extra);
+        }
+    }
+
     // A UI capture with no script VM would be a UI-less world under the scenario's name, so it
     // exits non-zero, as the window-size refusal does.
     if script.is_none() {