docs: purge chain-of-thought leakage from prose

Delete design-session citations (decision/audit/plan ordinals, stack
positions), change narration, review choreography, and reviewer-addressed
justification from comments, JSDoc, docs, READMEs, Agent Notes, tests, and
generator templates; restate every affected fact as current-state contract
prose. Fix generated docs at their sources and regenerate the catalogs and
cordis-surface regions; re-paste type-equiv blocks; update every bilingual
counterpart and re-record the pairs. Record the citation rule in the
committed-artifact-citations Agent Note.

packages/core/session/src/chunk-rows.ts

@@ -331,8 +331,7 @@ function expandRow(row: ChunkRow): SessionEvent[] {
  * Decode one parsed JSONL line value into the session event(s) it stores.
  * Chunk-row-tagged values validate and expand (a malformed row throws — it is
  * corrupt storage, and treating it as an event would silently drop a whole
- * run); every other value passes through as a single event, unvalidated,
- * exactly as readers treated event lines before packing existed.
+ * run); every other value passes through as a single event, unvalidated.
  *
  * @param value - one line's `JSON.parse` result.
  * @returns the stored events, in log order.

packages/core/session/src/types.ts

@@ -338,7 +338,8 @@ export type SurfaceEvent = SessionEvent<SurfaceEventType> & { surfaceOp: Surface
  *   (inclusive) through `end` (inclusive) with this node. Both must exist as
  *   surface nodes in the current surface. `start === end` replaces a single
  *   node. The node's {@link SessionEvent.sourceEventSeqs} must include every
- *   shadowed surface node. Used by compaction and possible other manipulations.
+ *   shadowed surface node. Used by compaction; any surface-replacing producer
+ *   may use it.
  */
 export type SurfaceOp =
   | 'append'