docs: pin working-state restore point (2026-05-17)

RESTORE.md documents the restore/working-2026-05-17 tag/branch
present in each of the 5 repos in the submodule chain, along with
restore commands. Snapshot of a known-good testnet sim state
before consolidation/refactoring.

Note: the restore tags were taken at the pre-consolidation commit
hashes — they preserve the original commit graph; this commit and
its consolidated peers live on top of those.

RESTORE.md

@@ -0,0 +1,66 @@
+# Restore point: working testnet sim — 2026-05-17
+
+Snapshot taken before consolidation / refactoring. Reproduces a passing
+testnet sim run in two modes:
+
+- **Default**: `SIM_NETWORK=testnet ./simulations/mix_lez_chat/run_simulation.sh --fresh`
+  — runs `run_setup` to create a fresh per-dev payment account, registers
+  all 5 sim participants on the deployed RLN tree, delivers test messages.
+- **Slim**: `SIM_NETWORK=testnet SIM_SLIM=1 ./simulations/mix_lez_chat/run_simulation.sh --fresh`
+  — skips `run_setup`; uses the shared payment account shipped in the
+  submodule. Useful for fresh-clone devs who don't want to build the
+  `lez-rln/run_setup` Rust binary.
+
+Both modes pass at ~2/3 reliability (intermittent mix-routing / QtRO flake;
+re-run with `--fresh` if a single attempt stalls).
+
+## Pinned commits (per repo)
+
+Each repo carries both an annotated tag and a branch named
+`restore/working-2026-05-17` at the listed commit. Either can be used to
+recover the state if HEAD moves during consolidation.
+
+| Repo | Branch when tagged | Commit |
+|---|---|---|
+| `.` (logos-chat) | `feat/sim-rln-gifter-auth-v2` | `b6f094e` |
+| `vendor/nwaku` | `feat/sim-rln-gifter-auth` | `60e875f3` |
+| `vendor/logos-lez-rln` | `feat/eip191-gifter-auth` | `ed88c8f8` |
+| `vendor/logos-lez-rln/logos-delivery-module` | `feat/eip191-gifter-auth` | `94173a3d` |
+| `vendor/logos-lez-rln/logos-delivery-module/vendor/logos-delivery` | `feat/eip191-gifter-auth` | `e2799efe` |
+
+## Restore
+
+```bash
+# From the outer repo root:
+for r in . vendor/nwaku vendor/logos-lez-rln \
+         vendor/logos-lez-rln/logos-delivery-module \
+         vendor/logos-lez-rln/logos-delivery-module/vendor/logos-delivery; do
+  git -C "$r" checkout restore/working-2026-05-17
+done
+```
+
+After checkout, rebuild affected nim/Rust artifacts:
+
+```bash
+# Rebuild liblogosdelivery (used by sim's delivery_module_plugin)
+( cd vendor/logos-lez-rln/logos-delivery-module/vendor/logos-delivery && make liblogosdelivery )
+
+# Rebuild run_setup (only needed for default mode, not slim)
+( cd vendor/logos-lez-rln/lez-rln && cargo build --bin run_setup )
+```
+
+## What's in this state
+
+- TREE_ID `…1a05100200000000` (2026-05-16 deploy #2) — programs deployed on
+  testnet, `is_initialized=true`.
+- `vendor/logos-lez-rln/testnet/storage.json.seed` ships full post-deploy
+  wallet state (10 accounts: 2 roots + 3 deploy publics + intermediate +
+  shared payment + 4 preconfigured).
+- `vendor/logos-lez-rln/testnet/{supply_holding,payment_account,config_account}.txt`
+  for the slim-mode bootstrap.
+- Gifter (mix node 0) self-registers as a mix relay at startup
+  (eliminates the "Plugin not ready" forwarding drop when sender's
+  circuit routes through it).
+- FFI aligned with SPEL `ConfigState` (240-byte borsh) + 4-field Register
+  instruction.
+- Cross-thread Nim heap-string race fix in `mix_lez_client`.