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+/**
+ * Hand-curated spell-slot / cantrip / repertoire progression overlay.
+ *
+ * WHY HAND-CURATED: Foundry pf2e encodes slot tables in description prose, not machine-
+ * readable rules (Pitfall #6 / verified 2026-04-27 against `wizard-spellcasting.json`).
+ * NLP-parsing prose is fragile; the canonical PF2e tables fit in ~300 lines and are stable
+ * across reprints.
+ *
+ * SOURCE: Archives of Nethys — Pathfinder 2e Player Core + Advanced Player's Guide
+ * (https://2e.aonprd.com). Per-class spell-slot tables, cantrip counts, and repertoire
+ * sizes (spontaneous casters only).
+ *
+ * SCOPE: 16 D-16 classes (Core + APG). This file (Plan 03) ships the type definitions
+ * and Wizard fully populated as the worked example. Plan 03b appends entries for the
+ * remaining 6 caster classes (Cleric, Druid, Witch, Bard, Sorcerer, Oracle) and the
+ * empty-array entries for non-casters.
+ *
+ * SPONTANEOUS vs PREPARED: Spontaneous casters (Bard, Sorcerer, Oracle) get
+ * repertoireIncrement entries on level-up. Prepared casters (Cleric, Druid, Witch, Wizard)
+ * get spellSlotIncrement only. Both get cantripIncrement at L1.
+ */
+
+export type SpellTradition = 'ARCANE' | 'DIVINE' | 'OCCULT' | 'PRIMAL';
+
+export interface SpellSlotOverlayEntry {
+  level: number;
+  spellSlotIncrement?: { tradition: SpellTradition; spellLevel: number; count: number };
+  cantripIncrement?: number;
+  repertoireIncrement?: number;
+}
+
+/**
+ * Each class maps to an array of overlay entries. Multiple entries per level are allowed
+ * (e.g. L1 Wizard gets 5 cantrips AND 2 grade-1 slots — two separate entries).
+ * Order within a level does not matter — the seed script merges them per (class, level).
+ */
+export const SPELL_SLOT_OVERLAY: Record<string, SpellSlotOverlayEntry[]> = {
+  // === PREPARED CASTER — WIZARD (worked example, fully populated in Plan 03) ===
+  Wizard: [
+    { level: 1, cantripIncrement: 5 },
+    { level: 1, spellSlotIncrement: { tradition: 'ARCANE', spellLevel: 1, count: 2 } },
+    { level: 2, spellSlotIncrement: { tradition: 'ARCANE', spellLevel: 1, count: 1 } },
+    { level: 3, spellSlotIncrement: { tradition: 'ARCANE', spellLevel: 2, count: 2 } },
+    { level: 4, spellSlotIncrement: { tradition: 'ARCANE', spellLevel: 2, count: 1 } },
+    { level: 5, spellSlotIncrement: { tradition: 'ARCANE', spellLevel: 3, count: 2 } },
+    { level: 6, spellSlotIncrement: { tradition: 'ARCANE', spellLevel: 3, count: 1 } },
+    { level: 7, spellSlotIncrement: { tradition: 'ARCANE', spellLevel: 4, count: 2 } },
+    { level: 8, spellSlotIncrement: { tradition: 'ARCANE', spellLevel: 4, count: 1 } },
+    { level: 9, spellSlotIncrement: { tradition: 'ARCANE', spellLevel: 5, count: 2 } },
+    { level: 10, spellSlotIncrement: { tradition: 'ARCANE', spellLevel: 5, count: 1 } },
+    { level: 11, spellSlotIncrement: { tradition: 'ARCANE', spellLevel: 6, count: 2 } },
+    { level: 12, spellSlotIncrement: { tradition: 'ARCANE', spellLevel: 6, count: 1 } },
+    { level: 13, spellSlotIncrement: { tradition: 'ARCANE', spellLevel: 7, count: 2 } },
+    { level: 14, spellSlotIncrement: { tradition: 'ARCANE', spellLevel: 7, count: 1 } },
+    { level: 15, spellSlotIncrement: { tradition: 'ARCANE', spellLevel: 8, count: 2 } },
+    { level: 16, spellSlotIncrement: { tradition: 'ARCANE', spellLevel: 8, count: 1 } },
+    { level: 17, spellSlotIncrement: { tradition: 'ARCANE', spellLevel: 9, count: 2 } },
+    { level: 18, spellSlotIncrement: { tradition: 'ARCANE', spellLevel: 9, count: 1 } },
+    // L19 Magnum Opus = 1 grade-10 slot per day
+    { level: 19, spellSlotIncrement: { tradition: 'ARCANE', spellLevel: 10, count: 1 } },
+    // L20: no slot increment (capstone is qualitative)
+  ],
+
+  // === STUBS — populated by Plan 03b ===
+  // Caster stubs (Plan 03b will replace [] with full L1..L20 entries):
+  Cleric: [],
+  Druid: [],
+  Witch: [],
+  Bard: [],
+  Sorcerer: [],
+  Oracle: [],
+  Champion: [], // focus-only; minimal entries
+
+  // Non-caster stubs (Plan 03b confirms these stay empty):
+  Alchemist: [],
+  Barbarian: [],
+  Fighter: [],
+  Investigator: [],
+  Monk: [],
+  Ranger: [],
+  Rogue: [],
+  Swashbuckler: [],
+};