docs: refine roadmap and article data architecture

PROJECT_KNOWLEDGE.md

@@ -221,6 +221,17 @@ Important data rule:
 - Article data is generated from ERP-derived sources.
 - These values should not be manually changed unless the task is explicitly data maintenance.
 
+Article-data architecture decision:
+
+- Article data should evolve from a simple article catalogue into a shared production knowledge base.
+- Each article may optionally provide production-related default values.
+- Initial defaults include `Product Thickness`, `Area Weight`, `Core Diameter`, and `Roll Width`.
+- Future production-related defaults can be added without changing the overall architecture.
+- When an article is selected, available defaults are copied into the calculator fields.
+- Missing optional values must never overwrite existing user input.
+- All automatically populated values remain editable by the user.
+- The planned Article-Data-Admin application will become the authoritative editor for these production defaults.
+
 Known domain caveat from existing project notes:
 
 - For articles in the groups Secugrid, Combigrid, Carbofol MF/MF, Carbofol F/F, Carbofol s/F, and Carbofol BF/s, the thickness from `article-data.json` must not be used without domain validation.

ROADMAP.md

@@ -15,3 +15,61 @@
 ## Version 0.5
 - Schnittstelle bzw. Import-/Deployment-Prozess zwischen externer Artikelverwaltungs-App und RollCalc definieren
 - Rollen-/Berechtigungskonzept für Zugriff auf RollCalc und externe Artikelverwaltung klären
+
+### Article Data and Selection Improvements
+
+- Article-specific production defaults
+  - Each article in `article-data.json` may optionally provide production-related default values.
+  - Initially planned defaults are `Product Thickness`, `Area Weight`, `Core Diameter`, and `Roll Width`.
+  - When an article is selected, available defaults should be copied into the existing calculator fields.
+  - Missing optional defaults must not clear or overwrite existing user input.
+  - Users must always be able to override suggested values manually.
+  - Stored `Core Diameter` values must match the values already allowed by the existing GUI control.
+  - `Roll Width` must be positive and plausible because it affects both `Roll Weight` and geometric loading in the `Load Optimizer`.
+  - The design should allow additional production-related defaults to be added later without changing the overall architecture. Possible future examples include preferred transport preset, minimum product length, maximum roll diameter, preferred rounding behavior, production restrictions, and handling limits.
+  - Maintenance of these defaults should be handled by the planned local Article-Data-Admin tool.
+  - Out of scope: deriving values from product group, production line, or site; multiple typical widths per article; multiple possible cores per article; locking manual edits; core load-bearing checks; line-dependent width checks; automatic `Roll Width` optimization.
+
+### Production Line and Site Rules
+
+- Define the data source and rule model for production-line- and site-dependent diameter limits.
+- This planning is separate from article-specific production defaults.
+
+### Documentation
+
+- Derive the German Quick Reference from the full User Manual.
+
+## Version 0.6
+
+### Roll Planning and Limits
+
+- Plan and validate minimum allowed `Product Length`.
+- Validate minimum and maximum `Roll Diameter` once a defined source for production-line and site rules exists.
+
+### Rounding and Production Logic
+
+- Configurable rounding for suggested `Product Length` at a given diameter.
+  - Allow rounding up or down.
+  - Make the step size configurable, for example 5 m increments.
+  - Rounding must not violate minimum product length or any other technical limit.
+
+### Documentation
+
+- Add the English Quick Reference based on the German Quick Reference and the language-aware Help structure.
+
+## Version 0.7
+
+### Handling and Safety Checks
+
+- Plan extended checks for `Roll Weight`.
+  - Forklift load capacity.
+  - Mandrel load capacity.
+  - Core load capacity.
+  - Additional relevant handling limits.
+  - Requires defined limits and data sources for forklift, mandrel, and core.
+
+### Result Export
+
+- PDF export for a concrete calculation result.
+  - Keep separate from the User Manual PDF export.
+  - Stabilize only after the result layout and exported metrics are defined.