Adds a Configuration page and makes click-to-copy opt-in, plus fixes found
by auditing the plugin against the Piwigo conventions.

Added
- Configuration page (Admin > Plugins > Album Suggest) using native
  admin-theme classes; saves via a pwg.albumsuggest.setConfig web-service
  method called by AJAX, no page reload.
- copy_on_click setting, default OFF. Clicking a suggestion no longer writes
  to the clipboard unless enabled; when off no click listener is attached and
  the rows carry no click affordance.
- French (fr_FR) translation; previously en_UK only.

Fixed
- Albums the current user may not see could appear as suggestions. All 9
  album-facing queries now carry get_sql_condition_FandF via a new
  albsug_cat_permission_sql() helper. admin_only is not sufficient: core's
  calculate_permissions() forbids un-granted private albums for every status.
  Unrestricted users are unaffected (the condition compiles to an empty
  string).
- pwg_token was sent by the client but never verified: the method didn't
  declare the parameter, so ws.php dropped it before the callback ran. Now
  declared and checked. Both ws methods are post_only.
- Missing index.php redirect guards in the plugin root and every subdirectory.

Changed
- Settings unserialized once in the init handler, so consumers get a plain
  array (matches core convention).
- uninstall() now removes the plugin's config key.