chore: point every in-tree reference at ai-job-search-dev/ai-job-search (#776)

The repository is moving from the MadsLorentzen personal account to the
ai-job-search-dev organization. GitHub redirects the old slug, but the
upstream-watch guard compares github.repository against the literal slug
and would start running the fork-only triage job on upstream itself, and
the upstream-check tool and its tests pin the slug too. README, CONTRIBUTING,
SECURITY, SETUP, the CI workflow, the issue-template config and the
CHANGELOG links follow.

Co-authored-by: Claude Fable 5.1 <noreply@anthropic.com>

.agents/skills/freehire-search/cli/src/helpers.ts

@@ -23,7 +23,7 @@ export function writeError(error: string, code: string): void {
 // cli/src, so a github.com URL here made every github.com link classify as an
 // installed job board instead of an unverified host. The owner/project name
 // already identifies the repo on GitHub.
-const UA = "MadsLorentzen/ai-job-search/1.0 (freehire-search)"
+const UA = "ai-job-search-dev/ai-job-search/1.0 (freehire-search)"
 
 /** The shared API response envelope: {data, meta, error}. */
 export interface Envelope<T> {