interop: ESP32 ↔ OpenWRT TollGate cross-platform test suite

- interop/Makefile: 10 targets for 4 test scenarios
  - interop-status: show device status for all devices
  - interop-laptop-esp32: laptop pays ESP32 with V3 token
  - interop-laptop-openwrt: laptop pays OpenWRT with V4 token
  - interop-openwrt-esp32: OpenWRT daemon auto-pays ESP32 upstream
  - interop-esp32-esp32: cross-board payment (needs Board B)
  - interop-setup/cleanup: mint alignment + wallet funding
- INTEROP_PLAN.md: full test plan with scenarios and token format details
- PROGRESS.md: checklist of setup/interop tasks
- AGENTS.md: standing instructions for interop testing
- routers.env.example: device config template
- Verified interop-status against real hardware (OpenWRT + ESP32 Board A)

1 files changed, 70 insertions, 0 deletions

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+# PROGRESS.md — Interop Test Checklist
+
+## Setup
+
+- [ ] Create `interop/routers.env` from `routers.env.example`
+- [ ] Verify SSH access to OpenWRT: `ssh root@10.47.41.1 echo ok`
+- [ ] Verify WiFi connection to ESP32: `ping -c 2 10.192.45.1`
+- [ ] Build `mint-token` binary: `cd physical-router-test-automation/scripts/mint-token && go build -o /tmp/mint-token .`
+- [ ] Install `cashu` CLI: `pip install cashu`
+
+## Mint Alignment
+
+- [ ] Add `testnut.cashu.space` to OpenWRT's `accepted_mints`
+- [ ] Add `nofee.testnut.cashu.space` to ESP32's config
+- [ ] Verify both mints accepted on OpenWRT
+- [ ] Verify both mints accepted on ESP32
+
+## Wallet Funding
+
+- [ ] Fund ESP32 wallet via `cashu send --legacy` (V3 token)
+- [ ] Fund OpenWRT wallet via `mint-token` (V4 token)
+- [ ] Verify ESP32 balance > 0
+- [ ] Verify OpenWRT balance > 0
+
+## Scenario 1: Laptop → ESP32
+
+- [ ] `make interop-laptop-esp32` — mint V3 token, POST to ESP32, verify internet
+- [ ] Token accepted (kind=1022)
+- [ ] Internet works after payment
+- [ ] Spent token rejected (kind=21023)
+
+## Scenario 2: Laptop → OpenWRT
+
+- [ ] `make interop-laptop-openwrt` — mint V4 token, POST to OpenWRT, verify internet
+- [ ] Token accepted (kind=1022)
+- [ ] Internet works after payment
+- [ ] Spent token rejected (kind=21023)
+
+## Scenario 3: OpenWRT → ESP32 (Reseller)
+
+- [ ] `make interop-openwrt-esp32` — OpenWRT connects to ESP32 AP, auto-pays
+- [ ] OpenWRT STA connects to `TollGate-C0E9CA`
+- [ ] OpenWRT daemon detects TollGate upstream
+- [ ] Auto-payment succeeds (ESP32 session created)
+- [ ] OpenWRT has internet through ESP32
+- [ ] ESP32 wallet balance increased
+- [ ] Cleanup: restore OpenWRT upstream
+
+## Scenario 5: ESP32 ↔ ESP32
+
+- [ ] Flash Board B with different nsec
+- [ ] Configure Board B's config.json
+- [ ] Fund Board B wallet
+- [ ] `make interop-esp32-esp32` — cross-board payment
+- [ ] Cleanup: restore both boards
+
+## Cleanup
+
+- [ ] Restore OpenWRT production config
+- [ ] Restore ESP32 original config (if changed)
+- [ ] Verify both devices back to normal operation
+
+## Infrastructure
+
+- [x] `interop/INTEROP_PLAN.md` written
+- [ ] `interop/AGENTS.md` written
+- [ ] `interop/routers.env.example` written
+- [ ] `interop/Makefile` written
+- [ ] `interop-status` target tested against real hardware
+- [ ] Committed and pushed