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).

backend/src/services/customerAccountsService.js

@@ -2,7 +2,7 @@
  * Customer Accounts Service
  *
  * Recurring user logins (the third user tier alongside admin and guest).
- * See discussion the-luap/picpeak#354 and migration 087 for context.
+ * See discussion PicPeak/picpeak#354 and migration 087 for context.
  *
  * Mirrors userManagementService.js for invitation lifecycle but operates
  * on customer_accounts / customer_invitations / event_customer_assignments

backend/src/services/environmentService.js

@@ -154,7 +154,7 @@ function generateUpdateInstructions(env, targetVersion) {
       {
         description: 'Download release archive',
         command: `# Download v${targetVersion} from GitHub Releases`,
-        note: `https://github.com/the-luap/picpeak/releases/tag/v${targetVersion}`
+        note: `https://github.com/PicPeak/picpeak/releases/tag/v${targetVersion}`
       },
       {
         description: 'Backup current installation',

backend/src/services/updateCheckService.js

@@ -94,7 +94,7 @@ async function fetchAvailableVersions() {
   try {
     // Use GitHub Releases API (public, no auth required)
     const response = await axios.get(
-      'https://api.github.com/repos/the-luap/picpeak/releases',
+      'https://api.github.com/repos/PicPeak/picpeak/releases',
       {
         headers: {
           'Accept': 'application/vnd.github+json',

backend/src/services/updateNotificationService.js

@@ -129,7 +129,7 @@ async function checkAndNotifyUpdates() {
 
     // Send email to each recipient
     const frontendUrl = process.env.FRONTEND_URL || 'http://localhost:3000';
-    const releaseNotesUrl = `https://github.com/the-luap/picpeak/releases/tag/v${newVersion}`;
+    const releaseNotesUrl = `https://github.com/PicPeak/picpeak/releases/tag/v${newVersion}`;
     const channelLabel = updateInfo.channel === 'beta' ? 'Beta' : 'Stable';
 
     let successCount = 0;