feat: squelette de l'extension Read More (config, i18n)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

configure.phtml

@@ -0,0 +1,23 @@
+<?php
+declare(strict_types=1);
+/** @var ReadMoreExtension $this */
+?>
+<form action="<?= _url('extension', 'configure', 'e', urlencode($this->getName())) ?>" method="post">
+	<input type="hidden" name="_csrf" value="<?= FreshRSS_Auth::csrfToken() ?>" />
+	<div class="form-group">
+		<label class="group-name" for="collapsed_height"><?= _t('ext.read_more.height.label') ?></label>
+		<div class="group-controls">
+			<input type="number" id="collapsed_height" name="collapsed_height"
+				value="<?= $this->getCollapsedHeight() ?>"
+				min="<?= ReadMoreExtension::MIN_HEIGHT ?>" max="<?= ReadMoreExtension::MAX_HEIGHT ?>" step="10" />
+			<p class="help"><?= _i('help') ?> <?= _t('ext.read_more.height.help') ?></p>
+		</div>
+	</div>
+
+	<div class="form-group form-actions">
+		<div class="group-controls">
+			<button type="submit" class="btn btn-important"><?= _t('gen.action.submit') ?></button>
+			<button type="reset" class="btn"><?= _t('gen.action.cancel') ?></button>
+		</div>
+	</div>
+</form>