New timeline event renderer: add new modules (#7721)

* Added HTML parser to abstract tree nodes

* Add HTML renderer using `HtmlMessageContent`

* Add custom rendering for inline code nodes besides the monospace font

* Support `<s>` and `<strike>` too

* Add `ContentAvoidingLayoutData` support

* Improve the last block node behaviour and its integration with `ContentAvoidingLayout`

* Move `ContentAvoidingLayout` to `:libraries:ui-common` so it can be shared

* Add missing `:libraries:htmlrenderer:impl` entry in `DependencyHandlerScope.allLibrariesImpl`

* Update screenshots

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Co-authored-by: ElementBot <android@element.io>

libraries/htmlrenderer/test/build.gradle.kts

@@ -0,0 +1,18 @@
+/*
+ * Copyright (c) 2026 Element Creations Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+plugins {
+    id("io.element.android-library")
+}
+
+android {
+    namespace = "io.element.android.libraries.htmlrenderer.test"
+}
+
+dependencies {
+    implementation(projects.libraries.htmlrenderer.api)
+    implementation(projects.tests.testutils)
+}

libraries/htmlrenderer/test/src/main/kotlin/io/element/android/libraries/htmlrenderer/test/FakeHtmlMessageParser.kt

@@ -0,0 +1,19 @@
+/*
+ * Copyright (c) 2026 Element Creations Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.htmlrenderer.test
+
+import io.element.android.libraries.htmlrenderer.api.DocumentNode
+import io.element.android.libraries.htmlrenderer.api.HtmlMessageParser
+import io.element.android.tests.testutils.lambda.lambdaError
+import org.jsoup.nodes.Document
+
+class FakeHtmlMessageParser(
+    private val parseResult: (Document) -> DocumentNode = { lambdaError() },
+) : HtmlMessageParser {
+    override fun parse(document: Document): DocumentNode = parseResult(document)
+}