feat(print-log): per-row delete on Print Log page (#1687 part 1)

Reporter noted the existing "Also remove this print from Quick Stats"
  toggle at archive delete is one-shot: if you kept stats then, there was
  no later way to drop the row; and rows without a backing archive
  (errors, aborts, manual entries) had no delete affordance at all.

  Backend: DELETE /print-log/{entry_id} mirrors delete_archive's
  ownership flow via require_ownership_permission(ARCHIVES_DELETE_ALL,
  ARCHIVES_DELETE_OWN). Owners drop their own rows; admins drop any row;
  missing IDs return 404 rather than 200-silently. /archives/stats
  aggregates over PrintLogEntry, so the filament / time / cost / count
  contribution drops out of Quick Stats in the same response cycle. The
  linked archive (if any) is untouched - the log row is a sibling, not a
  child.

  Frontend: trash icon next to the filament cell on every row, gated on
  the same permission shape as the archive trash. Confirm modal -> row
  gone. Mutation invalidates both print-log and archives-stats query
  keys so the totals re-render without a manual refresh.

  #1687 also asks for per-row tagging (already covered by
  EditArchiveModal's tags field) and per-row filament-usage-history
  edits (deferred - "restore deducted grams" is only consistent for the
  most recent usage row per spool; needs a separate design call).

frontend/src/api/client.ts

@@ -4364,6 +4364,8 @@ export const api = {
   getPrintLogThumbnail: (id: number) => withStreamToken(`${API_BASE}/print-log/${id}/thumbnail`),
   clearPrintLog: () =>
     request<{ deleted: number }>('/print-log/', { method: 'DELETE' }),
+  deletePrintLogEntry: (id: number) =>
+    request<{ status: string; id: number }>(`/print-log/${id}`, { method: 'DELETE' }),
 
   // Settings
   getSettings: () => request<AppSettings>('/settings/'),