docs: Document SMTP port 2465 support for implicit TLS (#1188)

[Open this suggestion in Promptless to view citations and reasoning
process](https://app.gopromptless.ai/change-history/f3f4cc12-c710-4d2d-96cd-e5443c52c8f1)

Updates the Email Configuration documentation to mention that port 2465
is now supported alongside port 465 for implicit TLS (SMTPS)
connections. Also clarifies the terminology: 587 uses STARTTLS while
465/2465 use implicit TLS from byte 1.

### Trigger Events

<details>
<summary><a
href="02c67ef532...2288c9c65c">stack-auth/stack-auth
commit (dev): 2288c9c Port 2465 should have implicit TLS from byte
1</a></summary>
<br>

**Promptless Research** (1 webpage)

- [Read webpage from
github.com](02c67ef532...2288c9c65c)

**Agent Response**

> I've completed my analysis and created a documentation suggestion for
this commit.
> 
> ## Summary
> 
> The commit `2288c9c` adds port 2465 as a supported implicit TLS
(SMTPS) port alongside the existing port 465. This is a small but
meaningful fix for users who use non-standard SMTP ports.
> 
> ## Documentation Change
> 
> I created a suggestion that updates the **Email Configuration**
section in the Emails guide:
> 
> **Before:**
> > Port: SMTP port (typically 587 for TLS or 465 for SSL)
> 
> **After:**
> > Port: SMTP port (typically 587 for STARTTLS, or 465/2465 for
implicit TLS)
> 
> This change:
> 1. Documents the newly supported port 2465 for implicit TLS
connections
> 2. Clarifies the terminology (STARTTLS vs implicit TLS) to be more
technically precise
> 
> The suggestion is available for review at:
https://app.gopromptless.ai/change-history/f3f4cc12-c710-4d2d-96cd-e5443c52c8f1

</details>



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Co-authored-by: promptless[bot] <179508745+promptless[bot]@users.noreply.github.com>
Co-authored-by: Madison <madison.w.kennedy@gmail.com>

docs/content/docs/(guides)/apps/emails.mdx

@@ -141,7 +141,7 @@ For production, configure your own SMTP server through the dashboard:
 - Select "Custom SMTP server" as your email server type
 - Configure the following settings:
   - **Host**: Your SMTP server hostname (e.g., `smtp.yourprovider.com`)
-  - **Port**: SMTP port (typically 587 for TLS or 465 for SSL)
+  - **Port**: SMTP port (typically 587 for STARTTLS, or 465/2465 for implicit TLS)
   - **Username**: Your SMTP username
   - **Password**: Your SMTP password
   - **Sender Email**: The email address emails will be sent from