systems rework: buffs, prestige graph, research, modular architecture

Decouples core systems from centralized globals in favor of catalogue-based architecture and data-driven content.

   Key changes:
   - Prestige: node-based buff tech tree, graph panel, progress bar
   - Research: multi-worker system, per-generator research, xp generation
   - Ascension: meta-currency layer via multi-currency prestige resets
   - Buffs: refactored as generator-independent via catalogues
   - UI: currency panel, edge-scrolling camera + zoom, current-goal panel
   - Alchemy Tower: crafting building with recipe/cost system
   - Testing: 7 test suites (ascension, prestige, research, goals)
   - Content: migrated from hardcoded idles/ to gym format (tiny_sword)

core/research/worker_summary_label.tscn

@@ -0,0 +1,8 @@
+[gd_scene format=3 uid="uid://ckr8z5xqy6h4w"]
+
+[ext_resource type="Script" path="res://core/research/worker_summary_label.gd" id="1_script"]
+
+[node name="WorkerSummaryLabel" type="Label"]
+layout_mode = 2
+script = ExtResource("1_script")
+text = "Workers: 0"