fix(navigation): let CSS size the nav logo and drop the inline width cap

The navbar logo carried an inline `height:36px;width:auto;max-width:{logo_width}px`
while `.navbar-logo > img` already owns `height:36px;padding:0 30px`. Under
`box-sizing:border-box` that max-width capped the border box, so the 60px of
horizontal padding stayed inside it and wide logos were squeezed against a
fixed height, breaking the intrinsic aspect ratio.

- Render the nav logo with no inline sizing; CSS alone sizes it.
- Add a `$lazy` argument to jio_get_adaptive_theme_img() so the navbar can emit
  the real src up front instead of a square lazyload placeholder; defaults to
  'auto' so every other caller keeps the lazy_other behaviour.
- Remove the superseded logo_width plumbing: the setting (PHP + VUE schemas),
  Settings::logo_width(), jio_get_site_logo_width(), the --jio-logo-width token
  and the unused has_logo context key.
- Cover the contract in the header reference test.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

inc/helpers/header/jio-header-render.php

@@ -41,14 +41,12 @@ if (!function_exists('jio_get_header_nav_context')) :
 		$brand_name  = $brand_name !== '' ? $brand_name : $site_name;
 		$logo_url    = function_exists('jio_get_site_logo_url') ? trim((string) jio_get_site_logo_url()) : '';
 		$logo_dark   = function_exists('jio_get_site_logo_dark_url') ? trim((string) jio_get_site_logo_dark_url()) : '';
-		$logo_width  = function_exists('jio_get_site_logo_width') ? jio_get_site_logo_width() : 150;
-		$logo_more   = $logo_width > 0
-			? 'style="height:36px;width:auto;max-width:' . max(36, (int) $logo_width) . 'px"'
-			: 'style="height:36px;width:auto"';
+		// 尺寸由 .navbar-logo > img 统一控制（height:36px / width:auto），
+		// 不叠加内联 max-width，否则 border-box 下的水平内边距会挤压图片。
 		$logo_html   = '';
 		if ($logo_url !== '' || $logo_dark !== '') {
 			$logo_html = function_exists('jio_get_adaptive_theme_img')
-				? jio_get_adaptive_theme_img($logo_url, $logo_dark, $brand_name, $logo_more)
+				? jio_get_adaptive_theme_img($logo_url, $logo_dark, $brand_name, '', false)
 				: '';
 		}
 
@@ -80,7 +78,6 @@ if (!function_exists('jio_get_header_nav_context')) :
 			'scroll_down_hide' => (!isset($settings['nav_scroll_down_hide']) || !empty($settings['nav_scroll_down_hide'])) && $nav_fixed,
 			'brand_name'       => $brand_name,
 			'logo_html'        => $logo_html,
-			'has_logo'         => $logo_html !== '',
 			'theme_positions'  => is_array($theme_positions) ? $theme_positions : [],
 			'can_publish'      => $can_publish,
 			'show_slide'       => $show_slide,

inc/helpers/template-tags/media-brand.php

@@ -104,35 +104,20 @@ function jio_get_site_logo_text(): string {
 }
 endif;
 
-if (!function_exists('jio_get_site_logo_width')):
-/**
- * 获取导航 Logo 宽度
- *
- * @return int
- */
-function jio_get_site_logo_width(): int {
-    if (class_exists('\Jio\Settings\Settings')) {
-        return \Jio\Settings\Settings::logo_width();
-    }
-
-    $width = (int) jio_get_setting('logo_width', 150);
-    return max(50, min(400, $width));
-}
-endif;
-
 if (!function_exists('jio_get_adaptive_theme_img')):
 /**
  * Build a single light/dark adaptive image (legacy white-src/dark-src contract).
  *
  * theme.js syncThemeImages() swaps src via white-src / dark-src attributes.
  *
- * @param string $white_src Light mode image URL.
- * @param string $dark_src  Dark mode image URL.
- * @param string $alt       Alt text.
- * @param string $more      Extra attributes (already escaped by caller if needed).
+ * @param string       $white_src Light mode image URL.
+ * @param string       $dark_src  Dark mode image URL.
+ * @param string       $alt       Alt text.
+ * @param string       $more      Extra attributes (already escaped by caller if needed).
+ * @param string|bool  $lazy      'auto' follows lazy_other; false renders the real src up front.
  * @return string
  */
-function jio_get_adaptive_theme_img(string $white_src = '', string $dark_src = '', string $alt = '', string $more = ''): string {
+function jio_get_adaptive_theme_img(string $white_src = '', string $dark_src = '', string $alt = '', string $more = '', $lazy = 'auto'): string {
     $white_src = trim($white_src);
     $dark_src  = trim($dark_src);
 
@@ -148,6 +133,9 @@ function jio_get_adaptive_theme_img(string $white_src = '', string $dark_src = '
     if ($alt === '') {
         $alt = get_bloginfo('name');
     }
+    if ($lazy === 'auto') {
+        $lazy = jio_is_lazy('lazy_other');
+    }
 
     $is_dark = false;
     if (class_exists('\Jio\Settings\Settings') && method_exists('\Jio\Settings\Settings', 'initial_theme_mode')) {
@@ -155,6 +143,10 @@ function jio_get_adaptive_theme_img(string $white_src = '', string $dark_src = '
     }
     $this_src = $is_dark ? $dark_src : $white_src;
 
-    return '<img' . jio_get_lazy_attr('lazy_other', (string) $this_src) . ' white-src="' . esc_url($white_src) . '" dark-src="' . esc_url($dark_src) . '" alt="' . esc_attr($alt) . '"' . ($more !== '' ? ' ' . $more : '') . '>';
+    $src_attr = $lazy
+        ? jio_get_lazy_attr('lazy_other', (string) $this_src)
+        : ' src="' . esc_url((string) $this_src) . '"';
+
+    return '<img' . $src_attr . ' white-src="' . esc_url($white_src) . '" dark-src="' . esc_url($dark_src) . '" alt="' . esc_attr($alt) . '"' . ($more !== '' ? ' ' . $more : '') . '>';
 }
 endif;