Enforce Genarrative play-type SOP and update docs

Rewrite Genarrative play-type integration guidance across .codex and .hermes to define a platform-level SOP: default to form/image workbench, unify single-image asset slots (CreativeImageInputPanel), standardize series-material sheet->cut->transparent->OSS pipeline, and forbid copying legacy chat/agent workflows as the default. Add decision-log entry freezing the SOP and a pitfalls note warning against direct reuse of old play tools. Update CONTEXT.md and docs/README.md, add a new PRD file, and apply related small server-side changes (module-auth, spacetime-client mappers and runtime) to align back-end code with the new contracts and flows.

server-rs/crates/api-server/src/match3d/draft.rs

@@ -532,7 +532,9 @@ fn build_config_from_message(
     }
 }
 
-pub(super) fn resolve_config_or_default(config: Option<&Match3DCreatorConfigRecord>) -> Match3DConfigJson {
+pub(super) fn resolve_config_or_default(
+    config: Option<&Match3DCreatorConfigRecord>,
+) -> Match3DConfigJson {
     config
         .map(|config| Match3DConfigJson {
             theme_text: config.theme_text.clone(),
@@ -595,7 +597,10 @@ fn build_match3d_assistant_reply(config: &Match3DConfigJson) -> String {
     )
 }
 
-pub(super) fn build_match3d_assistant_reply_for_turn(config: &Match3DConfigJson, current_turn: u32) -> String {
+pub(super) fn build_match3d_assistant_reply_for_turn(
+    config: &Match3DConfigJson,
+    current_turn: u32,
+) -> String {
     match current_turn {
         0 => MATCH3D_QUESTION_THEME.to_string(),
         1 => MATCH3D_QUESTION_CLEAR_COUNT.to_string(),