Prepare canonical party and derived players inputs

docs/integrations/notarius.md

@@ -41,6 +41,12 @@ selector, as direct argument-vector entries without shell interpretation. A CLI
 binding takes precedence over a matching external path in Notarius
 configuration. Narratio never emits `--without-reference`.
 
+For canonical party configuration, the `party` binding is the unchanged,
+validated authored roster and the `players` binding is its generated
+projection. Both retain their established `narratio.input.party` and
+`narratio.input.players` source IDs, and both are resolved from the prepared
+manifest rather than from campaign configuration at extraction time.
+
 The maintained D&D boundary binds only the four campaign-owned external slots:
 
 ```text

docs/integrations/party.md

@@ -47,3 +47,27 @@ must not override their party or players inputs.
 
 Use the canonical document for new campaigns. The configuration rules and
 source-relative path behavior are defined in the [Configuration Reference](../config.md).
+
+## Derived players document
+
+During `prepare`, Narratio copies the canonical party source bytes unchanged
+to `inputs/party.yml` and writes this deterministic players-only projection to
+`inputs/players.yml`:
+
+```yaml
+schema_version: narratio.players.v1
+players:
+    - name: Eric
+      character:
+        id: arannis
+        name: Arannis
+        alias:
+            - Ari
+            - The Grey Owl
+```
+
+There is one entry per character, sorted by stable character ID. Repeated
+player names remain separate entries. The optional `alias` list retains its
+declared order and is omitted when empty. The projection carries no class
+data. Its prepared manifest record is marked `derived_from_party`; it is not a
+separate user-provided `players_file`.