Implemented new campaign/session stable inputs and corresponding input source references

internal/config/scriptorium_test.go

@@ -215,6 +215,27 @@ func TestScriptoriumLoadAndValidate(t *testing.T) {
         transcript_markdown:
           source: narratio.transcript.final_markdown
           required: true
+`,
+		},
+		{
+			name: "prepared stable input sources are accepted",
+			scriptoriumYAML: `scriptorium:
+  binary: scriptorium
+  artifacts:
+    session_recap:
+      enabled: true
+      prompt_id: dnd.session_recap
+      output_path: artifacts/session_recap.md
+      inputs:
+        players:
+          source: narratio.input.players
+          required: true
+        party:
+          source: narratio.input.party
+          required: true
+        glossary:
+          source: narratio.input.glossary
+          required: false
 `,
 		},
 		{
@@ -575,4 +596,6 @@ inputs:
   speakers_file: ./speakers.yml
   autocorrect_file: ./autocorrect.yml
   glossary_file: ./glossary.yml
+  players_file: ./players.yml
+  party_file: ./party.yml
 `