# Specification: Correct Navidrome Database and Plugins Location (`fix_navidrome_paths`)

## Overview
Force Navidrome to use the `/data` LiteFS mount for its SQLite database by setting the `DATAFOLDER` to `/data`. To avoid the "Operation not permitted" error caused by LiteFS's restriction on directory creation, redirect the Navidrome plugins folder to persistent shared storage.

## Functional Requirements
- **Nomad Job Configuration (`navidrome-litefs-v2.nomad`):**
    - Set `ND_DATAFOLDER="/data"`. This will force Navidrome to create and use `navidrome.db` on the LiteFS mount.
    - Set `ND_PLUGINSFOLDER="/shared_data/plugins"`. This prevents Navidrome from attempting to create a `plugins` directory in the read-only/virtual `/data` mount.
    - Keep `ND_CACHEFOLDER` and `ND_BACKUP_PATH` pointing to `/shared_data` subdirectories.
- **Entrypoint Logic (`entrypoint.sh`):**
    - Ensure it creates `/shared_data/plugins` if it doesn't exist.
    - Remove the explicit `export ND_DATABASE_PATH` if it conflicts with the new `DATAFOLDER` logic, or keep it as an explicit override.
- **Verification:**
    - Confirm via `lsof` that Navidrome is finally using `/data/navidrome.db`.
    - Confirm that LiteFS `/debug/vars` now reports the database in its active set.

## Non-Functional Requirements
- **Persistence:** Ensure all non-database files (plugins, cache, backups) are stored on the shared host mount (`/shared_data`) to survive container restarts and migrations.

## Acceptance Criteria
- [ ] Navidrome successfully starts with `/data` as its data folder.
- [ ] No "Operation not permitted" errors occur during startup.
- [ ] `lsof` confirms `/data/navidrome.db` is open by the Navidrome process.
- [ ] LiteFS `txid` increases on the Primary and replicates to Replicas when Navidrome writes to the DB.