refactor: move unraid-specific tools into Plugin/unraid/tools/

api_cache_writer, remote_arr_cache_writer, conf_populate, storage_migrate are
all Unraid-adapter-specific — they read Docker appdata paths, Unraid service
configs, and drive the Unraid web plugin cache. They don't belong in Tools/.

- Tools/{4 scripts + php} → Plugin/unraid/tools/
- Fix source depth: ../ → ../../../ (now 3 levels from repo root)
- Fix conf_populate SCRIPTS_ROOT bug: was never set, would expand to empty
- api/arrs.php, api/storage.php: SCRIPTS_DIR/Tools/ → dirname(__DIR__)/tools/
- schedule.json: key IDs updated to Plugin/unraid/tools/...
- Cron rebuilt — live entries updated immediately

Plugin/unraid/tools/api_cache_writer.sh

@@ -0,0 +1,18 @@
+#!/bin/bash
+# ==============================================================================================
+# ================================= API Cache Writer ===========================================
+# ==============================================================================================
+#
+# PURPOSE
+# ─────────────────────────────────────────────────────────────────────────────
+# Builds the monitor and arrs API payloads and writes them to /tmp/vv_cache/
+# so page loads can serve from the file instantly instead of making live HTTP
+# calls on every request.
+#
+# Runs every minute via the Varaverk scheduler. /tmp is tmpfs — files are
+# RAM-speed reads and auto-cleared on reboot.
+#
+# ==============================================================================================
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+php "$SCRIPT_DIR/api_cache_writer.php"