Merge remote-tracking branch 'origin/master' into session-surface

Reconciles the session-surface work (surfaceOp/sourceEventSeqs provenance as
the sole derivation path) with master's worktree-subagent series (fork-seed
boundary + out-of-process subagent backends).

Semantic reconciliations beyond the textual auto-merge:
- SQLite SCHEMA_VERSION: both sides bumped 2->3. Merged to a single v3 carrying
  BOTH column families — master's seed_length on `sessions` and surface's
  source_event_seqs/surface_op on `events`. writeRow + both INSERT sites bind
  the full set; the schema doc lists all three added columns as the v2->v3 gap.
- agent-loop runStep request: master's `sessionId: session.id` and surface's
  per-append surfaceOp/sourceEventSeqs coexist (different regions).
- Fork seed + surface: a fork seeds the child from the parent's LIVE events,
  which now carry surfaceOp, so the child's surface rebuilds correctly. Verified
  end-to-end — the subagent-fork replay recalls the inherited "SAFFRON" codeword
  through the seeded prefix.
- Subagent snapshot fixtures (recorded pre-surface) re-enriched via KEYLESS
  deterministic replay: only surfaceOp/sourceEventSeqs added onto existing
  recorded lines (matched by seq), no recorded value changed. Not re-recorded
  against the live API.

Gates: typecheck, test (1112), test:snapshot (14), doc-sync, lint, build,
hygiene all green.

packages/session-persistence/session-persistence-jsonl/package.json

@@ -5,17 +5,19 @@
   "private": true,
   "type": "module",
   "main": "lib/index.js",
-  "types": "lib/index.d.ts",
+  "types": "lib/types/index.d.ts",
   "exports": {
     ".": {
-      "types": "./lib/index.d.ts",
+      "types": "./lib/types/index.d.ts",
       "default": "./lib/index.js"
     },
     "./src/*": "./src/*",
     "./package.json": "./package.json"
   },
   "files": [
-    "lib",
+    "lib/index.js",
+    "lib/types/**/*.d.ts",
+    "lib/types/**/*.d.ts.map",
     "src"
   ],
   "license": "BSD-3-Clause",

packages/session-persistence/session-persistence-jsonl/src/format.ts

@@ -24,6 +24,7 @@ export interface HeaderLine {
   createdAt: number
   cwd?: string
   parentSession?: SessionId
+  seedLength?: number
 }
 
 /** Build the header line object from a {@link SessionHeader}. */
@@ -35,6 +36,7 @@ export function toHeaderLine(header: SessionHeader): HeaderLine {
     createdAt: header.createdAt,
     ...header.cwd !== undefined ? { cwd: header.cwd } : {},
     ...header.parentSession !== undefined ? { parentSession: header.parentSession } : {},
+    ...header.seedLength !== undefined ? { seedLength: header.seedLength } : {},
   }
 }
 
@@ -46,6 +48,7 @@ export function fromHeaderLine(line: HeaderLine): SessionHeader {
     createdAt: line.createdAt,
     ...line.cwd !== undefined ? { cwd: line.cwd } : {},
     ...line.parentSession !== undefined ? { parentSession: line.parentSession } : {},
+    ...line.seedLength !== undefined ? { seedLength: line.seedLength } : {},
   }
 }
 

packages/session-persistence/session-persistence-jsonl/tsconfig.json

@@ -2,7 +2,7 @@
   "extends": "../../../tsconfig.base.json",
   "compilerOptions": {
     "rootDir": "src",
-    "outDir": "lib"
+    "outDir": "lib/types"
   },
   "include": [
     "src"