Add Optius scraper via its official RSS feed

Optius publishes an RSS feed with region/field filters, so no HTML
scraping is needed. Also move the duplicated slug helper into http.ts
(output unchanged, so existing source IDs and URLs are unaffected).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

scrapper/src/scrapers/adecco.ts

@@ -1,4 +1,4 @@
-import { USER_AGENT } from "./http";
+import { slugify, USER_AGENT } from "./http";
 import type { ScrapedJob, Scraper } from "./types";
 
 // Adecco has no public API, but its job search page loads results from this internal JSON endpoint
@@ -28,12 +28,7 @@ interface AdeccoResponse {
 
 /** The site builds "<title>-<location>/<jobid>" URLs; only the job ID matters, the slug is cosmetic. */
 function jobUrl(j: AdeccoJob): string {
-  const slug = `${j.jobTitle}-${j.jobLocation ?? ""}`
-    .normalize("NFD")
-    .replace(/[̀-ͯ]/g, "")
-    .replace(/[^A-Za-z0-9]+/g, "-")
-    .replace(/^-|-$/g, "")
-    .toLowerCase();
+  const slug = slugify(`${j.jobTitle}-${j.jobLocation ?? ""}`);
   return `${JOB_PAGE}/${slug}/${j.jobId.toLowerCase()}`;
 }