Support Python 3.14 template strings for HTML formatting

[MaddyGuthridge]

References:

• https://youtu.be/_QYAoNCK574
• https://peps.python.org/pep-0750/

Ideally, this would allow for HTML tags to be safely embedded within template strings.

>>> p.p(t"Bruno is {p.em("always")} hungry!")
<p>Bruno is <em>always</em> hungry</p>

In particular, note how with an f-string, the value would be escaped, resulting in incorrect output.

>>> p.p(f"Bruno is {p.em("always")} hungry!")
<p>Bruno is &lt;em&gt;always&lt;/em&gt; hungry</p>