feat(roles): add rclone-mount role for WebDAV mounts

Add a new system-level role for mounting WebDAV filesystems via rclone.
Includes rclone-torbox-setup helper script that uses rbw to bootstrap
credentials from Bitwarden.

Key features:
- Configurable WebDAV URL, username, mount point
- VFS cache mode and buffer size tuning for media streaming
- RequiresMountsFor option for ZFS pool dependencies
- Obscured password storage via environment file

Enable on john-endesktop for TorBox WebDAV access by rdt-client and
Jellyfin. Mount waits for /media ZFS pool before starting.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

roles/default.nix

@@ -14,6 +14,7 @@ with lib;
     ./nfs-mounts
     ./nvidia
     ./printing
+    ./rclone-mount
     ./remote-build
     ./spotifyd
     ./users

roles/rclone-mount/default.nix

@@ -0,0 +1,149 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+let
+  cfg = config.roles.rclone-mount;
+
+  # Generate systemd service for a single mount
+  mkMountService = name: mountCfg: {
+    description = "rclone mount for ${name}";
+    after = [ "network-online.target" ];
+    wants = [ "network-online.target" ];
+    wantedBy = [ "multi-user.target" ];
+
+    # Wait for parent mount points (e.g., ZFS pools) to be available
+    unitConfig = mkIf (mountCfg.requiresMountsFor != []) {
+      RequiresMountsFor = mountCfg.requiresMountsFor;
+    };
+
+    serviceConfig = {
+      Type = "notify";
+      ExecStartPre = "${pkgs.coreutils}/bin/mkdir -p ${mountCfg.mountPoint}";
+      ExecStart = concatStringsSep " " ([
+        "${pkgs.rclone}/bin/rclone mount"
+        ":webdav:${mountCfg.remotePath}"
+        "${mountCfg.mountPoint}"
+        "--webdav-url=${mountCfg.webdavUrl}"
+        "--webdav-vendor=${mountCfg.webdavVendor}"
+        "--webdav-user=${mountCfg.username}"
+        "--allow-other"
+        "--vfs-cache-mode=${mountCfg.vfsCacheMode}"
+        "--dir-cache-time=${mountCfg.dirCacheTime}"
+        "--poll-interval=${mountCfg.pollInterval}"
+        "--log-level=${mountCfg.logLevel}"
+      ] ++ mountCfg.extraArgs);
+      ExecStop = "${pkgs.fuse}/bin/fusermount -uz ${mountCfg.mountPoint}";
+      Restart = "on-failure";
+      RestartSec = "10s";
+      EnvironmentFile = mountCfg.environmentFile;
+    };
+  };
+in
+{
+  options.roles.rclone-mount = {
+    enable = mkEnableOption "Enable rclone WebDAV mounts";
+
+    mounts = mkOption {
+      type = types.attrsOf (types.submodule {
+        options = {
+          webdavUrl = mkOption {
+            type = types.str;
+            description = "WebDAV server URL (e.g., https://webdav.torbox.app)";
+          };
+
+          webdavVendor = mkOption {
+            type = types.enum [ "other" "nextcloud" "owncloud" "sharepoint" "sharepoint-ntlm" "fastmail" ];
+            default = "other";
+            description = "WebDAV server vendor for optimizations";
+          };
+
+          username = mkOption {
+            type = types.str;
+            description = "WebDAV username (often email address)";
+          };
+
+          environmentFile = mkOption {
+            type = types.path;
+            description = ''
+              Path to environment file containing RCLONE_WEBDAV_PASS.
+              The password should be obscured using: rclone obscure <password>
+              File format: RCLONE_WEBDAV_PASS=<obscured_password>
+            '';
+          };
+
+          mountPoint = mkOption {
+            type = types.str;
+            description = "Local mount point path";
+          };
+
+          remotePath = mkOption {
+            type = types.str;
+            default = "/";
+            description = "Remote path on WebDAV server to mount";
+          };
+
+          vfsCacheMode = mkOption {
+            type = types.enum [ "off" "minimal" "writes" "full" ];
+            default = "full";
+            description = ''
+              VFS cache mode. For streaming media, 'full' is recommended.
+              - off: No caching (direct reads/writes)
+              - minimal: Cache open files only
+              - writes: Cache writes and open files
+              - full: Full caching of all files
+            '';
+          };
+
+          dirCacheTime = mkOption {
+            type = types.str;
+            default = "5m";
+            description = "Time to cache directory entries";
+          };
+
+          pollInterval = mkOption {
+            type = types.str;
+            default = "1m";
+            description = "Poll interval for remote changes";
+          };
+
+          logLevel = mkOption {
+            type = types.enum [ "DEBUG" "INFO" "NOTICE" "ERROR" ];
+            default = "INFO";
+            description = "rclone log level";
+          };
+
+          extraArgs = mkOption {
+            type = types.listOf types.str;
+            default = [];
+            description = "Extra arguments to pass to rclone mount";
+          };
+
+          requiresMountsFor = mkOption {
+            type = types.listOf types.str;
+            default = [];
+            description = ''
+              List of mount points that must be available before this service starts.
+              Use this when the mount point's parent is on a ZFS pool or other filesystem
+              that may not be mounted at boot time.
+              Example: [ "/media" ] to wait for the media ZFS pool to mount.
+            '';
+          };
+        };
+      });
+      default = {};
+      description = "Attribute set of rclone WebDAV mounts to configure";
+    };
+  };
+
+  config = mkIf cfg.enable {
+    # Ensure FUSE is available
+    environment.systemPackages = [ pkgs.rclone pkgs.fuse ];
+    programs.fuse.userAllowOther = true;
+
+    # Create systemd services for each mount
+    systemd.services = mapAttrs' (name: mountCfg:
+      nameValuePair "rclone-mount-${name}" (mkMountService name mountCfg)
+    ) cfg.mounts;
+  };
+}