Add NPC registry grounding for spell extraction

docs/internal/modules.md

@@ -25,8 +25,9 @@ of that set; input and output builders receive no references. The spell
 extractor is typed over the canonical D&D model. D&D validators, merge, and
 normalize use typed variants; JSON representation validators use serialized
 requests; and unconditional validators expose separate chunk and typed
-variants. The D&D production registrar registers only the canonical typed spell
-implementations.
+variants. The D&D production registrar registers the canonical typed spell and
+NPC implementations, including their kind-specific merge and normalize
+behavior.
 
 Prepared extractors, extract validators, and codecs may be reused concurrently
 by the run-wide extract pool. Production implementations are immutable after
@@ -81,6 +82,15 @@ semantic digest; overlay content remains contextual reference material rather
 than source evidence. Its external JSON contract is defined in the
 [spell-catalog overlay contract](../integrations/dnd-spell-catalog-overlays.md).
 
+### `internal/modules/dnd/npcs/identity` and `internal/modules/dnd/codec/npcs`
+
+The NPC identity package owns Unicode comparison keys, deterministic
+`npc:sha256:` IDs, display normalization, and whole-registry collision issues.
+The NPC codec owns the strict durable `dnd/npc-list` JSON boundary and exposes
+candidate versus approved encode/decode operations. NPC source references are
+durable provenance and may later be consumed by another pipeline as registry
+context without being treated as evidence for that pipeline.
+
 ## Input Adapter
 
 ### `internal/modules/seriatim/input/transcript`
@@ -186,9 +196,34 @@ stages, using the codec only for checkpoint, debug, and output boundaries.
 Shared D&D helpers keep prompt input
 names and source-unit reference conversion consistent with the scene chunker.
 
+The extractor also declares the optional `npcs` registry slot. Preparation
+requires one approved `application/json` item no larger than 1 MiB, validates
+identity without relating registry source references to the current transcript,
+and supplies canonical JSON to a spell-owned prompt message. A bound registry
+adds only `npc_registry_digest` and `npc_count` to manifest metadata and an
+`npc_registry` checkpoint fingerprint. The unbound prompt input is exactly
+`{"npcs":[]}` and has no registry provenance or fingerprint.
+
 The durable payload and manifest metadata shapes are defined in the
 [D&D spell artifact contract](../integrations/dnd-spell-artifacts.md).
 
+### `internal/modules/dnd/extract/npcs`
+
+The NPC extractor maps private model output to the canonical `dnd.NPCList`,
+assigns source identity and deterministic NPC IDs, and preserves source
+references for deterministic validation. It uses the shared campaign
+references only for disambiguation and does not consume the spell-owned NPC
+registry slot. Its prompt and private response schema are package-owned.
+
+### `internal/modules/dnd/normalize/npcs`
+
+The NPC normalizer performs deterministic identity-aware consolidation in
+merged input order. It unions only canonical identity or canonical/alias
+matches, retains the first display record, unions exact relationships and
+source references, rewrites unambiguous relationship targets, and leaves
+ambiguous collisions for identity validation. It exposes the identity policy
+as its local checkpoint fingerprint and emits bounded normalization warnings.
+
 ## Merger And Normalizer
 
 ### `internal/modules/generic/merge/appendorder`
@@ -272,6 +307,17 @@ are defined in
 payload rules are defined in the
 [artifact contract](../integrations/dnd-spell-artifacts.md).
 
+## D&D NPC Validators
+
+NPC shape validation checks required strings, arrays, and source-reference
+shape. The source-reference validator checks current-document identity, unit
+existence, and range ordering; source relatedness emits at most one bounded
+warning per record when neither the canonical name nor an alias occurs near
+its cited text. Normalize identity validation checks deterministic IDs,
+canonical names, aliases, and cross-record ownership or canonical collisions.
+All are deterministic and expose the policy fingerprints used by the
+production chains.
+
 ## Production Registration
 
 Production composition occurs through family registrars. The CLI allocates one
@@ -280,8 +326,8 @@ complete framework registry set and one LLM asset registry. It invokes
 `internal/modules/seriatim/register`, and `internal/modules/dnd/register` in
 that order, then exposes the matching catalog for resolution. The generic and
 Seriatim registrars own their production leaf registrations. The D&D registrar
-owns D&D leaf registrations, the typed spell default-validator chains, and D&D
-prompt/schema asset collection.
+owns D&D leaf registrations, typed spell and NPC default-validator chains,
+typed append-order specializations, and D&D prompt/schema asset collection.
 
 Concrete implementation packages do not import generic implementation
 packages directly. A concrete family's `register` package is its composition