Fix reading time not displaying in details partial

[delize]

Summary

• Fix .Site.Params.article.readingTime resolving to nil in details.html because the partial receives a dict context, not a page context
• Change to $Page.Site.Params.article.readingTime to match the pattern already used on lines 40 and 67 of the same file

Problem

The details.html partial is called with a dict:

{{ partial "article/components/details" (dict "Page" $Page "IsList" $IsList) }}

When . (dot) is a dict, .Site resolves to nil. This causes $showReadingTime to always be false, so the reading time is never rendered despite readingTime = true being set in site config.

Lines 40 and 67 of the same file already correctly use $Page.Site.Params — only line 31 was missed.

Test plan

• Verify readingTime = true in params.toml under [article]
• Build site and confirm <time class="article-time--reading"> appears in article HTML
• Confirm reading time displays on both list and single page views