Organize D&D extensions by domain

internal/modules/dnd/extract/spells/assets/prompts/instructions.md

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+Source references must use integer source-unit IDs from the transcript. Provide
+start_unit_id and end_unit_id for each source reference; the extractor assigns
+source_id automatically.
+
+Return only D&D spell-cast artifacts. For each spell cast, identify the in-world
+caster, spell name, effect, narrative description, and source references.
+
+Use player, party, and glossary reference material only to clarify source text.
+Do not return spells, casters, or effects that are mentioned only in reference
+material.
+
+Return exactly one JSON object and no explanatory text.