Say where the auto-seed flag can actually arrive

The recovered comment claimed a dev server picks the flag up from the
environment it was built with. It does not: dev and start both serve from src/,
so build.ts's define only reaches the staging bundle the @e2e harness builds.
OFF, the default and the reason the gate exists, needs no plumbing; opting IN
is what is out of reach, and closing that gap means making the app bootstrap
async, which nothing here needs yet.

src/shared/utils/autoSeed.ts

@@ -8,18 +8,26 @@
  * when explicitly enabled via the env var `FESTIPOD_AUTO_SEED` (= "1").
  *
  * Same compile-time plumbing as the shared-wallet password (sharedWallet.ts):
- * `build.ts` `define`s the global from the env var for a static bundle. Absent
- * env → global undefined → seed OFF.
+ * `build.ts` `define`s the global from the env var. Absent env → global
+ * undefined → seed OFF, which is the whole point: OFF needs no plumbing at all.
  *
  * RECOVERED FROM THE ng-eventually BRANCH, with two differences that branch does
- * not have:
- *  - there is no `/festipod-config.json` here, so the flag arrives at BUILD time
- *    only; a dev server picks it up from the environment it was built with;
- *  - `fixtureSeedEnabled()` below is NOT enforced in `bootstrapWallet` on this
- *    branch. On ng-eventually it switches every route off, which stands down the
- *    @data scenarios that seed; adopting that here is a product decision, not a
- *    side effect of recovering this file. Until it is taken, only the AUTOMATIC
- *    seed is gated — an explicit `loadTestData()` still writes.
+ * not have.
+ *
+ * TURNING IT ON ONLY REACHES A BUILT BUNDLE. `bun run dev` and `bun run start`
+ * both serve from `src/` (`src/index.ts` imports `index.html`), so the `define`
+ * in `build.ts` never reaches them — only `dist-staging/`, which the @e2e harness
+ * builds, is affected. ng-eventually closes that gap with a
+ * `/festipod-config.json` route read by `frontend.tsx` before the app loads;
+ * recovering it here means making the app bootstrap async, which is not needed
+ * for the gate's purpose (stopping the dev seed from bloating a persistent
+ * wallet) and is therefore left out until someone actually wants to opt in.
+ *
+ * `fixtureSeedEnabled()` BELOW IS NOT ENFORCED in `bootstrapWallet` here. On
+ * ng-eventually it switches every route off, which stands down the @data
+ * scenarios that seed; adopting that is a product decision, not a side effect of
+ * recovering this file. Until it is taken, only the AUTOMATIC seed is gated — an
+ * explicit `loadTestData()` still writes.
  */
 
 /**