chore(edit-content): add site field to search relationships (#31298)

### Parent Issue

#31280 

### Proposed Changes

This pull request introduces a new `SiteFieldComponent` for selecting a
site from a tree structure in the `dot-edit-content-relationship-field`
module. The changes include the implementation of the component, its
associated styles, unit tests, and a store for managing the component's
state.

Key changes:

### Component Implementation:
*
[`site-field.component.ts`](diffhunk://#diff-e4382792ef202b90112a6556f3c1d63c21e8f7c8f747f1cb09b77d25bfbccb1bR1-R129):
Added the `SiteFieldComponent` which implements `ControlValueAccessor`
to work with Angular forms and uses PrimeNG's `TreeSelect` component for
the UI.
*
[`site-field.component.html`](diffhunk://#diff-c61c7bf501226714ed8accbb0b61a025e57c0179affa0a1fc53159f1c05b76b2R1-R44):
Created the template for the `SiteFieldComponent` using `p-treeSelect`
for the tree structure and added error handling.
*
[`site-field.component.scss`](diffhunk://#diff-06646f7c6ecfc10412b89a98dd4935436d2e7d23feea988b0f4a557018d57b63R1-R7):
Added styles to ensure the `TreeSelect` component spans the full width
of its container.

### Unit Tests:
*
[`site-field.component.spec.ts`](diffhunk://#diff-520d6e974cad3c205627cc77b5a0ec56b334303f941a74a67554c2609dabdfddR1-R198):
Added comprehensive unit tests for the `SiteFieldComponent`, covering
initial state, control value accessor implementation, and edge cases.
*
[`site-field.store.spec.ts`](diffhunk://#diff-810b776b9ac7916a02ef0ab369f0584f5018a2a7d8750e18c0ea99e8ec344cf4R1-R253):
Added unit tests for the `SiteFieldStore`, ensuring proper loading of
sites, handling of errors, and state management.

### Checklist
- [x] Tests
- [x] Translations
- [x] Security Implications Contemplated (add notes if applicable)

core-web/libs/dotcms-webcomponents/src/elements/dot-contentlet-thumbnail/dot-contentlet-thumbnail.tsx

@@ -117,9 +117,9 @@ export class DotContentletThumbnail {
     }
 
     private getIcon() {
-        return this.contentlet?.baseType !== 'FILEASSET'
-            ? this.contentlet?.contentTypeIcon
-            : this.contentlet?.__icon__;
+        return this.contentlet?.baseType === 'FILEASSET'
+            ? this.contentlet?.__icon__
+            : this.contentlet?.contentTypeIcon;
     }
 
     private shouldShowVideoThumbnail() {

core-web/libs/edit-content/src/lib/fields/dot-edit-content-relationship-field/components/dot-select-existing-content/components/search/components/site-field/site-field.component.html

@@ -0,0 +1,44 @@
+<label for="language-field" class="mb-2 inline-block">
+    {{ 'dot.file.relationship.dialog.search.site.label' | dm }}
+</label>
+
+<p-treeSelect
+    (onNodeSelect)="store.chooseNode($event)"
+    (onNodeExpand)="store.loadChildren($event)"
+    [formControl]="siteControl"
+    data-testid="site-field-search"
+    [filter]="true"
+    [options]="store.tree()"
+    [virtualScroll]="true"
+    [virtualScrollItemSize]="50"
+    [scrollHeight]="'450px'"
+    [placeholder]="'dot.file.relationship.dialog.search.site.placeholder' | dm"
+    [virtualScrollOptions]="{
+        autoSize: true,
+        style: {
+            width: '100%',
+            height: '450px',
+            minHeight: '200px'
+        }
+    }"
+    filterBy="label"
+    filterMode="lenient"
+    selectionMode="single">
+    <ng-template let-node pTemplate="default">
+        <span>{{ node?.label | truncatePath }}</span>
+    </ng-template>
+    <ng-template let-item pTemplate="value">
+        @if (item?.label) {
+            <span>//{{ item?.label }}</span>
+        } @else {
+            <span>{{ 'dot.file.relationship.dialog.search.site.placeholder' | dm }}</span>
+        }
+    </ng-template>
+</p-treeSelect>
+
+@let error = store.error();
+@if (error) {
+    <div class="text-red-500 text-sm mt-2">
+        {{ error | dm }}
+    </div>
+}

core-web/libs/edit-content/src/lib/fields/dot-edit-content-relationship-field/components/dot-select-existing-content/components/search/components/site-field/site-field.component.scss

@@ -0,0 +1,7 @@
+:host {
+    ::ng-deep {
+        .p-treeselect {
+            width: 100%;
+        }
+    }
+}

core-web/libs/edit-content/src/lib/fields/dot-edit-content-relationship-field/components/dot-select-existing-content/components/search/components/site-field/site-field.component.spec.ts

@@ -0,0 +1,198 @@
+import { createFakeEvent } from '@ngneat/spectator';
+import { Spectator, createComponentFactory, mockProvider } from '@ngneat/spectator/jest';
+import { of } from 'rxjs';
+
+import { ReactiveFormsModule } from '@angular/forms';
+
+import { TreeSelectModule } from 'primeng/treeselect';
+
+import { DotMessageService } from '@dotcms/data-access';
+import {
+    TreeNodeItem,
+    TreeNodeSelectItem
+} from '@dotcms/edit-content/models/dot-edit-content-host-folder-field.interface';
+import { TruncatePathPipe } from '@dotcms/edit-content/pipes/truncate-path.pipe';
+import { DotEditContentService } from '@dotcms/edit-content/services/dot-edit-content.service';
+import { DotMessagePipe } from '@dotcms/ui';
+import { MockDotMessageService } from '@dotcms/utils-testing';
+
+import { SiteFieldComponent } from './site-field.component';
+import { SiteFieldStore } from './site-field.store';
+
+describe('SiteFieldComponent', () => {
+    let spectator: Spectator<SiteFieldComponent>;
+    let component: SiteFieldComponent;
+    let store: InstanceType<typeof SiteFieldStore>;
+
+    const messageServiceMock = new MockDotMessageService({
+        'dot.file.relationship.dialog.search.language.failed': 'Failed to load languages'
+    });
+
+    const mockSites: TreeNodeItem[] = [
+        {
+            label: 'demo.dotcms.com',
+            data: {
+                id: '123',
+                hostname: 'demo.dotcms.com',
+                path: '',
+                type: 'site'
+            },
+            icon: 'pi pi-globe',
+            leaf: false,
+            children: []
+        }
+    ];
+
+    const mockFolders = {
+        parent: {
+            id: 'parent-id',
+            hostName: 'demo.dotcms.com',
+            path: '/parent',
+            addChildrenAllowed: true
+        },
+        folders: [
+            {
+                label: 'folder1',
+                data: {
+                    id: 'folder1',
+                    hostname: 'demo.dotcms.com',
+                    path: 'folder1',
+                    type: 'folder' as const
+                },
+                icon: 'pi pi-folder',
+                leaf: true,
+                children: []
+            }
+        ]
+    };
+
+    const createComponent = createComponentFactory({
+        component: SiteFieldComponent,
+        imports: [ReactiveFormsModule, TreeSelectModule, TruncatePathPipe, DotMessagePipe],
+        componentProviders: [SiteFieldStore],
+        providers: [
+            { provide: DotMessageService, useValue: messageServiceMock },
+            mockProvider(DotEditContentService, {
+                getSitesTreePath: jest.fn().mockReturnValue(of(mockSites)),
+                getFoldersTreeNode: jest.fn().mockReturnValue(of(mockFolders))
+            })
+        ]
+    });
+
+    beforeEach(() => {
+        spectator = createComponent({
+            detectChanges: false
+        });
+        component = spectator.component;
+        store = spectator.inject(SiteFieldStore, true);
+    });
+
+    it('should create', () => {
+        spectator.detectChanges();
+
+        expect(component).toBeTruthy();
+    });
+
+    describe('Initial State', () => {
+        it('should initialize with empty site control', () => {
+            spectator.detectChanges();
+
+            expect(component.siteControl.value).toBe('');
+        });
+
+        it('should load sites on init', () => {
+            const loadSitesSpy = jest.spyOn(store, 'loadSites');
+
+            spectator.detectChanges();
+
+            expect(loadSitesSpy).toHaveBeenCalled();
+        });
+    });
+
+    describe('ControlValueAccessor Implementation', () => {
+        const testValue = 'test-site-id';
+
+        it('should write value to form control', () => {
+            spectator.detectChanges();
+
+            component.writeValue(testValue);
+            expect(component.siteControl.value).toBe('');
+        });
+
+        it('should register onChange callback', () => {
+            const onChangeSpy = jest.fn();
+            component.registerOnChange(onChangeSpy);
+
+            const mockEvent: TreeNodeSelectItem = {
+                originalEvent: createFakeEvent('click'),
+                node: {
+                    label: 'Test Node',
+                    data: { id: '123', hostname: 'test.com', path: 'test', type: 'folder' }
+                }
+            };
+
+            store.chooseNode(mockEvent);
+            spectator.detectChanges();
+
+            expect(onChangeSpy).toHaveBeenCalledWith(mockEvent.node.data.id);
+        });
+
+        it('should register onTouched callback', () => {
+            const onTouchedSpy = jest.fn();
+            component.registerOnTouched(onTouchedSpy);
+
+            // Trigger touched state
+            component.siteControl.markAsTouched();
+            spectator.detectChanges();
+
+            // Note: Since we're not explicitly calling onTouched in the component,
+            // this test mainly verifies the registration
+            expect(onTouchedSpy).not.toHaveBeenCalled();
+        });
+
+        describe('Disabled State', () => {
+            it('should disable the form control', () => {
+                component.setDisabledState(true);
+                expect(component.siteControl.disabled).toBe(true);
+            });
+
+            it('should enable the form control', () => {
+                // First disable
+                component.setDisabledState(true);
+                expect(component.siteControl.disabled).toBe(true);
+
+                // Then enable
+                component.setDisabledState(false);
+                expect(component.siteControl.disabled).toBe(false);
+            });
+        });
+    });
+
+    describe('Edge Cases', () => {
+        it('should handle undefined value in writeValue', () => {
+            component.writeValue(undefined);
+            expect(component.siteControl.value).toBe('');
+        });
+
+        it('should handle null value in writeValue', () => {
+            component.writeValue(null);
+            expect(component.siteControl.value).toBe('');
+        });
+
+        it('should handle empty string in writeValue', () => {
+            component.writeValue('');
+            expect(component.siteControl.value).toBe('');
+        });
+
+        it('should not emit change when writeValue is called with same value', () => {
+            const onChangeSpy = jest.fn();
+            component.registerOnChange(onChangeSpy);
+
+            const testValue = 'test-value';
+            component.writeValue(testValue);
+            component.writeValue(testValue);
+
+            expect(onChangeSpy).not.toHaveBeenCalled();
+        });
+    });
+});