feat: add jobbasel.ch and englishjobsearch.ch job sources

jobbasel.ch's search route (/job/suche-{slug}) is server-rendered with
a window.__PRELOADED_STATE__ JSON blob, no headless browser needed.
englishjobsearch.ch works the same way via its ?format=markdown param.
Both swept with the same fixed keyword list job-room.ch already uses.

basel-jobs.ch was evaluated too but left out: it's DataDome-protected,
which blocks plain curl outright, and this project's fetchers are
intentionally browser-free.

While wiring these in, found that isEnglishDescription (now
isViableDescription) only ever ran the DE/FR word-count check against
inline descriptions, never requiresGerman() - so an English-written
posting demanding fluent German (e.g. PRODYNA's "you can communicate
fluently in both German and English") sailed straight through. That
gap existed in itjobs.ch and job-room.ch too, not just the two new
sources, so the fix applies to all four.

fetch.ts

@@ -158,7 +158,7 @@ const GERMAN_OPTIONAL_RE =
 
 /** Within a mention's window: signals it is genuinely required at B2+. */
 const GERMAN_REQUIRED_RE =
-  /\b(?:required|require[sd]?|must|mandatory|essential|necessary|fluent|fluency|proficien\w*|excellent|strong|very\s+good|good\s+(?:knowledge|command|level)|native|mother\s*tongue|business\s+level|negotiat\w*|B2|C1|C2|verhandlungssicher\w*|fliessend|fließend|muttersprach\w*|sehr\s+gute?|gute?\s+Deutschkenntnisse|voraussetzung|zwingend)\b/i;
+  /\b(?:required|require[sd]?|must|mandatory|essential|necessary|fluen\w*|proficien\w*|excellent|strong|very\s+good|good\s+(?:knowledge|command|level)|native|mother\s*tongue|business\s+level|negotiat\w*|B2|C1|C2|verhandlungssicher\w*|fliessend|fließend|muttersprach\w*|sehr\s+gute?|gute?\s+Deutschkenntnisse|voraussetzung|zwingend)\b/i;
 
 /** Title-level marker — no description fetch needed. */
 export const GERMAN_TITLE_RE =