Feature request: include snippet code in the list-table search

The snippets list search matches name, description and tags, but not the code. On a site with a lot of snippets that means it cannot answer the question you most often have: which snippet is doing this?

To reproduce on 3.10.2: pick a string that appears only inside a snippet’s PHP, for example style_loader_tag, and search for it in the Search snippets box. Zero results. Name and description searches work normally, so the box looks like it covers everything.

Why it matters: on a site with 65 active snippets I was tracking down which one was inlining stylesheets. The search returned nothing, which read as proof that no snippet was responsible. One was, and I only found it by querying the snippets table directly. A search that silently excludes the largest field can send you the wrong way.

Suggestions, in order of preference: 1. Include the code column in the search. 2. If that would be too slow or too noisy by default, add a “search code” checkbox, or support a code: prefix. 3. Failing either, note the limitation next to the search box so a zero-result search is not misread.