chore: migrate Docker registry + GitHub URLs to PicPeak org

Repo transferred from the-luap/picpeak → PicPeak/picpeak. Docker images
publish to ghcr.io/picpeak/picpeak/{backend,frontend} (lowercase, per the
GHCR canonical form computed by docker-build.yml's `${GITHUB_REPOSITORY,,}`).

Sweep covers:
- docker-compose.production.yml + Dockerfiles → new image registry path
- README, CONTRIBUTING, SECURITY, SIMPLE_SETUP, scripts/picpeak-setup.sh
  → new GitHub URLs
- Update-check / release-notes services (updateCheckService,
  environmentService, updateNotificationService, adminSystem,
  UpdateNotification, githubReleaseUrl) → GitHub API + tag URLs use the
  canonical PicPeak/picpeak path
- Issue templates + README-DOCKER + workflow README → updated package URLs
- One commit-context comment in migrations/090 + customerAccountsService

CHANGELOG.md is intentionally untouched (historical release entries are
immutable; GitHub auto-redirects the old URLs indefinitely).
CLAUDE.md keeps the bare `(the-luap)` reference — that's the maintainer's
personal handle, not a repo URL.

22 files, 48/48 line swaps (every change is a 1:1 URL replacement).

SECURITY.md

@@ -16,7 +16,7 @@ We take the security of PicPeak seriously. If you have discovered a security vul
 ### 1. **Do NOT create a public GitHub issue**
 
 ### 2. Report the vulnerability privately by:
-- **Preferred:** Use [GitHub Private Vulnerability Reporting](https://github.com/the-luap/picpeak/security/advisories/new)
+- **Preferred:** Use [GitHub Private Vulnerability Reporting](https://github.com/PicPeak/picpeak/security/advisories/new)
 - **Alternative:** Email us at **[email protected]** with the details
 - Include:
   - Description of the vulnerability
@@ -82,7 +82,7 @@ We believe in responsible disclosure. Once a vulnerability is fixed:
 
 ## Contact
 
-- Security issues: Email **[email protected]** or use [GitHub Private Vulnerability Reporting](https://github.com/the-luap/picpeak/security/advisories/new)
-- General support: [GitHub Issues](https://github.com/the-luap/picpeak/issues)
+- Security issues: Email **[email protected]** or use [GitHub Private Vulnerability Reporting](https://github.com/PicPeak/picpeak/security/advisories/new)
+- General support: [GitHub Issues](https://github.com/PicPeak/picpeak/issues)
 
 Thank you for helping keep PicPeak and its users safe!