Add constraints to developer documentation

src/main/asciidoc/developer_documentation.adoc

@@ -74,10 +74,55 @@ The first column lists the quality demands, while in the following columns an "x
 |Portability              | x |   |   |   |
 |===
 
-== Randbedingungen
-* Hardware-Vorgaben
-* Software-Vorgaben
-* Vorgaben zum Betrieb des Software
+== Constraints
+
+Each constraint is annotated with b, r and/or u,
+each representing if it is a
+build-time (includes development),
+run-time (backend),
+or use-time (frontend)
+constraint.
+Use-time constraints can be separated into customer (c) and administration (a),
+each denoted by having their letter prefixed with `u.`.
+
+=== Hardware Specifications
+
+ * r: server computer
+ * b: mid-range computer
+ * u: computer
+ * b: input device for text
+ * u: input/output devices
+   ** pointing device
+     (e.g, mouse, TrackPoint™, digitizer, touch input)
+   ** text input device
+     (i.e. keyboard),
+     can be emulated (software/touch or for accessibility reasons)
+   ** u.a: screen with a resolution of at least 1920×1080 at a DPR of 1 (= 96 dpi)
+   ** u.c: screen with a resolution of at least 360×640/640×360 at a DPR of 1 (= 96 dpi)
+
+=== Software Specifications
+
+ * r: JRE 17
+ * b: JDK 17
+ * u: Any HTML5/CSS3 compatibly browser using one of the following engines (or a newer version)
+   ** Chromium 108
+   ** Firefox 115
+   ** WebKit 605.1.15
+   ** Explicity not supported are any browsers based on Trident/EdgeHTML
+
+=== Product Usage
+
+The system is going to to be used as a website for administration and handling of orders for the catering service operated by Hannes Wurst.
+
+The system is supposed to run on a server computer
+(a computer running 24/7 with a datacenter-grade internet connection)
+so that customers and the administrator can access it at any time.
+Its provided service is made available as a web site (HTML5/CSS3/ECMAScript over HTTP).
+Should the customer of the project require an encrypted connection using TLS,
+it is their responsibility to set up a reverse proxy in front of the system.
+
+It cannot be assumed that the users (customers and administrator) have a technical background,
+so common patterns that are easily learned should be used.
 
 == Kontextabgrenzung
 * Kontextdiagramm