feat: basic implementation of partial evaluator service (#649)

Closes partially #603

### Summary of Changes

* Add partial evaluator service. This replaces the old
`toConstantExpressionOrUndefined` function.
* Improve the model classes that represent evaluation results.
* Evaluate more types of expressions.
* Add more tests.

Still TODO in a future PR: Add tests for the model classes, particularly
for their `toString` and `equals` methods, and include them in the
coverage computation.

---------

Co-authored-by: megalinter-bot <129584137+megalinter-bot@users.noreply.github.com>

docs/development/partial-evaluation-testing.md

@@ -22,7 +22,7 @@ partial evaluation test.
    test marker, the second test comment corresponds to the second test marker, etc.
     * `// $TEST$ constant equivalence_class <id>`: Assert that all nodes with the same `<id>` get partially evaluated
       successfully to the same constant expression.
-    * `// $TEST$ constant serialization <value>`: Assert that the node gets partially evaluated to a constant expression
+    * `// $TEST$ serialization <value>`: Assert that the node gets partially evaluated to a constant expression
       that serializes to `<value>`.
     * `// $TEST$ not constant`: Assert that the node cannot be evaluated to a constant expression.
 6. Run the tests. The test runner will automatically pick up the new test.

package.json

@@ -18,7 +18,7 @@
     "galleryBanner": {
         "color": "#e3e9e9"
     },
-    "icon": "img/safe-ds_logo_rounded.png",
+    "icon": "img/safe-ds_logo_rounded_128x128.png",
     "homepage": "https://dsl.safeds.com",
     "qna": "https://github.com/orgs/Safe-DS/discussions",
     "bugs": {
@@ -60,7 +60,11 @@
                     ".sdsstub",
                     ".sdstest"
                 ],
-                "configuration": "./language-configuration.json"
+                "configuration": "./language-configuration.json",
+                "icon": {
+                    "light": "img/safe-ds_file_icon_light.svg",
+                    "dark": "img/safe-ds_file_icon_dark.svg"
+                }
             }
         ],
         "grammars": [

src/language/builtins/safe-ds-annotations.ts

@@ -5,8 +5,8 @@ import { resourceNameToUri } from '../../helpers/resources.js';
 import { URI } from 'langium';
 import { SafeDsServices } from '../safe-ds-module.js';
 import { SafeDsNodeMapper } from '../helpers/safe-ds-node-mapper.js';
-import { toConstantExpression } from '../partialEvaluation/toConstantExpression.js';
-import { ConstantExpression, ConstantString } from '../partialEvaluation/model.js';
+import { EvaluatedNode, StringConstant } from '../partialEvaluation/model.js';
+import { SafeDsPartialEvaluator } from '../partialEvaluation/safe-ds-partial-evaluator.js';
 
 const ANNOTATION_USAGE_URI = resourceNameToUri('builtins/safeds/lang/annotationUsage.sdsstub');
 const CODE_GENERATION_URI = resourceNameToUri('builtins/safeds/lang/codeGeneration.sdsstub');
@@ -15,11 +15,13 @@ const MATURITY_URI = resourceNameToUri('builtins/safeds/lang/maturity.sdsstub');
 
 export class SafeDsAnnotations extends SafeDsModuleMembers<SdsAnnotation> {
     private readonly nodeMapper: SafeDsNodeMapper;
+    private readonly partialEvaluator: SafeDsPartialEvaluator;
 
     constructor(services: SafeDsServices) {
         super(services);
 
         this.nodeMapper = services.helpers.NodeMapper;
+        this.partialEvaluator = services.evaluation.PartialEvaluator;
     }
 
     isDeprecated(node: SdsAnnotatedObject | undefined): boolean {
@@ -48,7 +50,7 @@ export class SafeDsAnnotations extends SafeDsModuleMembers<SdsAnnotation> {
 
     getPythonModule(node: SdsModule | undefined): string | undefined {
         const value = this.getArgumentValue(node, this.PythonModule, 'qualifiedName');
-        if (value instanceof ConstantString) {
+        if (value instanceof StringConstant) {
             return value.value;
         } else {
             return undefined;
@@ -61,7 +63,7 @@ export class SafeDsAnnotations extends SafeDsModuleMembers<SdsAnnotation> {
 
     getPythonName(node: SdsAnnotatedObject | undefined): string | undefined {
         const value = this.getArgumentValue(node, this.PythonName, 'name');
-        if (value instanceof ConstantString) {
+        if (value instanceof StringConstant) {
             return value.value;
         } else {
             return undefined;
@@ -92,11 +94,11 @@ export class SafeDsAnnotations extends SafeDsModuleMembers<SdsAnnotation> {
         node: SdsAnnotatedObject | undefined,
         annotation: SdsAnnotation | undefined,
         parameterName: string,
-    ): ConstantExpression | undefined {
+    ): EvaluatedNode {
         const annotationCall = findFirstAnnotationCallOf(node, annotation);
-        const expression = argumentsOrEmpty(annotationCall).find(
+        const argumentValue = argumentsOrEmpty(annotationCall).find(
             (it) => this.nodeMapper.argumentToParameterOrUndefined(it)?.name === parameterName,
         )?.value;
-        return toConstantExpression(expression);
+        return this.partialEvaluator.evaluate(argumentValue);
     }
 }