Standalone Shonar Desktop: vendor portable sources + local engine; decouple from ~/Projects/Shonar

- shared/ = portable Android-origin sources vendored from deferred/desktop-server
  (app/build.gradle.kts srcDir repointed; PlaybackController.kt excluded as Android-only)
- backend/ = bundled-lite engine (SQLite + inline queue); .venv symlinked from the
  old checkout, PYTHONPATH pins THIS backend's code over any editable install
- repoRoot() resolves this project dir (env SHONAR_REPO still wins); desktop-dev.sh
  watches shared/ + backend/
- Verified: :app:compileKotlin + :app:test green (23 tests); engine boots on :8010,
  self-migrates, /healthz ok

desktop-dev.sh

@@ -0,0 +1,60 @@
+#!/usr/bin/env bash
+# SHONAR desktop dev loop: runs the app and auto-restarts it when any
+# Kotlin/Gradle source changes (inotifywait). Engine runs in dev mode
+# (SHONAR_DEV=1 -> uvicorn --reload), so backend edits apply live too.
+#
+# Stop with Ctrl-C (or pkill -f desktop-dev.sh).
+set -uo pipefail
+cd "$(dirname "$0")"
+
+export SHONAR_DEV=1
+export DISPLAY="${DISPLAY:-:0}"
+
+FLAG="$(pwd)/.dev-restart-flag"
+
+# Watch targets resolved to absolute paths, non-existent dirs skipped at
+# start but retried each cycle (inotifywait -r tolerates a dir appearing).
+watch_targets() {
+  local t=()
+  for d in "$PWD/app/src/main/kotlin" \
+           "$PWD/shared/com/shonar" \
+           "$PWD/backend/shonar"; do
+    [ -d "$d" ] && t+=("$d")
+  done
+  printf '%s\n' "${t[@]}"
+}
+
+pkill -f "com.shonar.desktop.MainKt" 2>/dev/null || true
+rm -f "$FLAG"
+sleep 1
+
+(
+  while true; do
+    mapfile -t TARGETS < <(watch_targets)
+    [ ${#TARGETS[@]} -eq 0 ] && { sleep 5; continue; }
+    if inotifywait -qq -e close_write,move --include '\.kt$|\.kts$' \
+        -r "${TARGETS[@]}"; then
+      echo "[dev] source change -> restarting app…"
+      touch "$FLAG"
+      pkill -f "com.shonar.desktop.MainKt" 2>/dev/null || true
+      sleep 2   # debounce bursts (editor writes can fire several events)
+    else
+      sleep 5   # targets vanished; retry with a fresh list
+    fi
+  done
+) &
+WATCHER=$!
+trap 'kill $WATCHER 2>/dev/null || true; rm -f "$FLAG"' EXIT
+
+while true; do
+  rm -f "$FLAG"
+  ./gradlew run --offline
+  if [ -f "$FLAG" ]; then
+    continue                       # killed by a source edit: rebuild now
+  fi
+  rm -f "$FLAG"
+  # App closed cleanly or build failed — wait for the next edit.
+  mapfile -t TARGETS < <(watch_targets)
+  [ ${#TARGETS[@]} -eq 0 ] && { sleep 5; continue; }
+  inotifywait -qq -e close_write,move --include '\.kt$|\.kts$' -r "${TARGETS[@]}" || sleep 5
+done