feat: add InvenTree Cloudron package (Business-Apps) [#658]

Official-image wrapper of inventree/inventree 1.5.2 (digest-pinned).
allauth OIDC provider JSON built from the platform env; invoke update
on boot; RQ worker behind the web-port gate; admin seeded with a
generated password. grind-stack: lowercase image names. 19th package.
Verified: health 200, SSO route 302s to issuer, migrations clean.

Detail: https://projects.knownelement.com/issues/658#note-5086

README.md

@@ -9,9 +9,9 @@ The Cloudron component focuses on packaging upstream free/libre/open application
 ### 📊 Current Progress
 
 - **Total Applications**: 46 (see [GitUrlList.txt](GitUrlList.txt); pruned 2026-09-06 by human rulings: no-Node policy, k8s redirects, out-of-scope)
-- **Completed Packages**: 18/46 (~39% of the post-ruling set)
+- **Completed Packages**: 19/46 (~41% of the post-ruling set)
 - **Packaging Templates**: Created ✅
-- **Packages Committed & Pushed**: 18 ✅
+- **Packages Committed & Pushed**: 19 ✅
 - **Build Tickets**: rulings synced 2026-09-06 (#633-#678 batch, umbrella
   [#632](https://projects.knownelement.com/issues/632), Redmine project 55);
   grist-core excluded (packaged upstream)
@@ -40,6 +40,7 @@ The Cloudron component focuses on packaging upstream free/libre/open application
 | 16 | NetBox | Infrastructure | ~1GB | 8080 | localstorage, postgresql, redis | ✅ Committed |
 | 17 | ConsulDemocracy | Collaboration | ~1.6GB | 3000 | localstorage, postgresql | ✅ Committed |
 | 18 | GoAlert | Monitoring | ~40MB | 8081 | localstorage, postgresql | ✅ Committed |
+| 19 | InvenTree | Business-Apps | ~1.4GB | 8000 | localstorage, postgresql, redis | ✅ Committed |
 
 ### 📦 Packages in Development