refactor: collapse fakewallet/regtest wrappers into single dev CLI

Replaces the two parallel scripts (fakewallet.sh, regtest.sh) with one
modules/dev-env/scripts/dev.sh — `dev up [--fakewallet|--regtest]`,
plus `down|logs|shell`. Default mode is fakewallet (no docker, no
chains, instant), matching what the prior scaffold did with two scripts
but giving consumers one command and one verb-set to learn.

Drops the now-redundant `lnbits.backend` enum and `features.fakewallet`
option from core.nix. Backend selection is the dev CLI's runtime
concern; a NixOS-level option would be a second knob that can disagree
with the CLI flag at runtime. `lnbits.{host,port}` stay (bind addr,
useful to docs and any later service path). `features.regtest` stays
(gates docker engine installation — consumers who'll never use the
regtest mode shouldn't pay for the container engine).

Strips modules/lnbits.nix entirely. The dev CLI runs lnbits ad-hoc; if
a NixOS-managed lnbits service becomes a real ask later, re-add a
focused module then.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

modules/dev-env/scripts/dev.sh

@@ -0,0 +1,53 @@
+#!/usr/bin/env bash
+# dev — single entry point for spinning up an LNbits dev environment.
+#
+#   dev up [--fakewallet|--regtest]   start lnbits (default: --fakewallet)
+#   dev down                          tear down whatever's running
+#   dev logs                          follow lnbits (and docker, if regtest) logs
+#   dev shell                         drop into the lnbits venv (or regtest container)
+#
+# Modes:
+#   --fakewallet  (default)  LNBITS_BACKEND_WALLET_CLASS=FakeWallet — no docker,
+#                            no chains, instant. Good for extension / UI work.
+#   --regtest                docker-compose up the multi-node regtest stack
+#                            (LND + CLN + Eclair + bitcoind + electrs), then
+#                            start lnbits pointed at the LND-rest endpoint.
+#                            Wraps lnbits/legend-regtest-enviroment.
+#
+# Skeleton — no real wiring yet. The substantive pass will:
+#   - locate the lnbits checkout via inputs.lnbits-src (or a configurable path)
+#   - locate the regtest docker repo via config.lnbits-sensei.devEnv.regtest.repoUrl
+#   - bring up containers, wait-for-it, populate LND credentials, exec lnbits
+
+set -euo pipefail
+
+cmd="${1:-up}"
+shift || true
+
+mode="fakewallet"
+while [[ $# -gt 0 ]]; do
+  case "$1" in
+    --fakewallet) mode="fakewallet"; shift ;;
+    --regtest)    mode="regtest";    shift ;;
+    *) echo "dev: unknown flag: $1" >&2; exit 1 ;;
+  esac
+done
+
+case "$cmd" in
+  up)
+    echo "dev up --$mode: TODO — wire substantive startup in next pass."
+    ;;
+  down)
+    echo "dev down: TODO — wire teardown in next pass."
+    ;;
+  logs)
+    echo "dev logs: TODO — tail lnbits + (docker logs if regtest) here."
+    ;;
+  shell)
+    echo "dev shell: TODO — drop into venv / regtest container here."
+    ;;
+  *)
+    echo "Usage: dev {up|down|logs|shell} [--fakewallet|--regtest]" >&2
+    exit 1
+    ;;
+esac

modules/dev-env/scripts/fakewallet.sh

@@ -1,38 +0,0 @@
-#!/usr/bin/env bash
-# fakewallet.sh — symmetric no-op for parity with regtest.sh.
-#
-# FakeWallet is the default LNbits backend. There is nothing to start,
-# nothing to stop, nothing to log: LNbits with `LNBITS_BACKEND_WALLET_CLASS=FakeWallet`
-# just runs.
-#
-# This wrapper exists purely so the dev experience is symmetric with
-# the regtest stack:
-#
-#   fakewallet up      # no-op, prints reassurance
-#   fakewallet down    # no-op, prints reassurance
-#   fakewallet logs    # tails lnbits' own logs (not a backend's)
-#   fakewallet shell   # no-op (no container to enter)
-#
-# Muscle memory wins. `regtest up` and `fakewallet up` mean the same
-# thing — "make the chosen backend ready" — even when one is a docker
-# stack and the other is a constant.
-
-set -euo pipefail
-
-# TODO(skeleton): wire the substantive variants in a later pass.
-# `up` / `down` / `shell` stay no-ops by design; `logs` should
-# `journalctl --user -u lnbits` (or whatever unit the lnbits module
-# ends up declaring) so the dev still has a single place to look.
-
-case "${1:-up}" in
-  up | down | shell)
-    echo "FakeWallet is the default — nothing to start."
-    ;;
-  logs)
-    echo "fakewallet logs: TODO — tail the lnbits service log here."
-    ;;
-  *)
-    echo "Usage: fakewallet {up|down|logs|shell}"
-    exit 1
-    ;;
-esac

modules/dev-env/scripts/regtest.sh

@@ -1,36 +0,0 @@
-#!/usr/bin/env bash
-# regtest.sh — wrapper around a Bitcoin/Lightning regtest docker stack.
-#
-# Mirrors the workflow of `lnbits/legend-regtest-enviroment` (LND + CLN
-# + Eclair + bitcoind + electrs). Cloned to
-# `${dev-env.root}/local/docker/regtest/` by the bootstrap script
-# (later pass); this wrapper just dispatches `up` / `down` / `logs` /
-# `shell` to the underlying docker-compose stack.
-#
-# Symmetric with fakewallet.sh so the dev experience reads the same
-# whether you're on the default FakeWallet path or the regtest stack:
-#
-#   regtest up         # boot the regtest stack
-#   regtest down       # tear it down
-#   regtest logs       # tail compose logs
-#   regtest shell      # drop into a node container
-#
-# Once `regtest up` is healthy, point LNbits at the appropriate
-# backend (LndRestWallet / CoreLightningWallet) by flipping
-# `lnbits-sensei.lnbits.backend` and rebuilding.
-
-set -euo pipefail
-
-# TODO(skeleton): replace with real dispatcher in the substantive pass.
-# Intended shape:
-#   case "${1:-}" in
-#     up)    docker compose -f "${REGTEST_DIR}/docker-compose.yml" up -d ;;
-#     down)  docker compose -f "${REGTEST_DIR}/docker-compose.yml" down ;;
-#     logs)  docker compose -f "${REGTEST_DIR}/docker-compose.yml" logs -f ;;
-#     shell) docker compose -f "${REGTEST_DIR}/docker-compose.yml" exec "${2}" sh ;;
-#     *)     usage ;;
-#   esac
-
-echo "regtest: TODO — substantive implementation lands in a later pass."
-echo "See modules/dev-env/scripts/regtest.sh for the intended dispatcher shape."
-exit 0