refactor: add canonical transcript assembly seam

docs/adr/0001-parse-core-and-persist-layers.md

@@ -33,7 +33,9 @@ binding-agnostic and does not need a per-binding implementation.
   `IndexUnit` when correctness requires whole-unit semantics — for example,
   Codex duplicate reconciliation or Kimi `context.undo` / `context.clear`
   replay. Each adapter maps its own resume/change semantics onto the existing
-  `mtime` and `lines_processed` cursor pair in `index_state`.
+  `mtime` and `lines_processed` cursor pair in `index_state`. The emitted
+  `TranscriptRecord` stream is also the input to provider-independent session
+  detail assembly; see ADR-0007.
 - **Persist axis — one shared orchestration.** A single provider-agnostic,
   binding-agnostic layer consumes records from any adapter and writes them:
   incremental `index_state` bookkeeping, FTS maintenance, and the canonical
@@ -56,9 +58,9 @@ main process migrates to ESM (ADR-0003) to import the shared core. The real work
 is disentangling the currently interleaved parse-and-write inside `indexJsonl` /
 `indexCodexJsonl` into (pure adapter parse) + (shared persist).
 
-The SQLite schema and normalized `IndexRecord` union are the stable center of
-the design. Provider-only concepts are either projected lossily into that
-language or ignored; they do not add provider columns or tables. The registry,
+The normalized `TranscriptRecord` union is the stable center of the design, and
+SQLite is one serialization adapter for it. Provider-only concepts are either
+projected lossily into that language or ignored. The registry,
 not provider switches, drives both indexers, watcher roots, persisted source
 roots, source catalog/UI labels and colors, and raw-record routing. Adding Pi
 therefore changes the Pi adapter, its registration, and its conformance tests;