Deleting/updating file attachments fails with 404 — frontend calls singular attachment/{type}:{id} but OCS route is plural attachments/{id}

[GUMMIIII]

Describe the bug
Removing a file attachment (a file shared from Files, type: file) from a card via the sidebar (⋯ → Remove attachment) does nothing. The DELETE request returns HTTP 404 / OCS statuscode: 998 ("Invalid query"). The same mismatch affects updating and restoring attachments.

Steps to reproduce

Add a file to a card via "Share from Files" (creates a share_type 12 attachment).
Open the card, ⋯ on the attachment → Remove attachment.
Nothing happens; the Network tab shows a failed DELETE.

Actual request (fails):
DELETE /ocs/v2.php/apps/deck/api/v1.0/cards/52/attachment/file:198?boardId=7
→ 404, {"ocs":{"meta":{"status":"failure","statuscode":998,"message":"Invalid query, ..."}}}

Root cause
The frontend AttachmentApi builds the URL with singular attachment/ and a composite type:id:
// src/services/attachment.js (as shipped in js/deck-main.js)
async deleteAttachment(attachment, boardId) {
await axios({ method: 'DELETE',
url: this.ocsUrl(/cards/${attachment.cardId}/attachment/${attachment.type}:${attachment.id}),
params: { boardId: boardId ?? null } })
}
// updateAttachment() and restoreAttachment() use the same singular attachment/${type}:${id} scheme

But the OCS routes register delete/update/restore under plural attachments/{attachmentId} with type as a separate parameter:
// appinfo/routes.php (ocs)
['name' => 'attachment_ocs#delete', 'url' => '/api/v{apiVersion}/cards/{cardId}/attachments/{attachmentId}', 'verb' => 'DELETE'],
// AttachmentOcsController::delete(int $cardId, int $attachmentId, string $type = 'file', ?int $boardId = null)

So the singular path matches no OCS route → 998/404. (createAttachment POST /cards/{cardId}/attachment and getAll /cards/{cardId}/attachments both match fine — only delete/update/restore are inconsistent.)

Confirmed working call (proves the backend is fine, only the frontend URL is wrong):
DELETE /ocs/v2.php/apps/deck/api/v1.0/cards/52/attachments/198?type=file&boardId=7
→ 200 OK (share removed, source file kept)

Suggested fix
Align the frontend AttachmentApi delete/update/restore to /cards/${cardId}/attachments/${attachment.id} and pass type via params (matching the OCS controller). The shipped 1.18.2 JS bundle appears out of sync with the OCS routes.

Server configuration

Nextcloud: 34.0.1
Deck: 1.18.2 (files verified against the official signature.json — unmodified)
DB: MySQL · PHP 8.x · nginx (YunoHost)
Browser: Chrome 149