Fix center alignment of IAM policy example label in BYOLLM docs (#43)

* Fix center alignment of IAM policy example label in BYOLLM docs

Convert standalone bold text '**Example: AWS Bedrock minimum IAM policy**' to a
proper '####' heading so Astro Starlight renders it left-aligned instead of centered.

Co-Authored-By: Oz <oz-agent@warp.dev>

* Fix all code blocks center-aligned due to figure CSS rule

The .sl-markdown-content figure rule in custom.css applied text-align: center
to all figures, including the <figure> elements that Expressive Code renders
for code blocks. This caused every code block on the site to be center-aligned.

Fix by scoping the rule to exclude .expressive-code figures, so only image
figures (used for screenshot captions) get the centered treatment.

Co-Authored-By: Oz <oz-agent@warp.dev>

---------

Co-authored-by: Oz <oz-agent@warp.dev>

Author: IsaiahWitzke

src/content/docs/enterprise/enterprise-features/bring-your-own-llm.mdx

@@ -81,9 +81,7 @@ In the [Admin Panel](/enterprise/team-management/admin-panel/), configure which
 
 Grant your team members the necessary permissions in AWS. Use least-privilege IAM policies.
 
-**Example: AWS Bedrock minimum IAM policy**
-
-```json
+```json title="Example: AWS Bedrock minimum IAM policy"
 {
   "Version": "2012-10-17",
   "Statement": [

src/styles/custom.css

@@ -277,8 +277,11 @@ body {
 
    Caption editorial rules (see AGENTS.md § "Image caption guidelines"):
    Orient the reader, don't instruct. Keep under ~20 words. No marketing
-   language. Don't repeat surrounding prose or list everything visible. */
-.sl-markdown-content figure {
+   language. Don't repeat surrounding prose or list everything visible.
+
+   Exclude Expressive Code figures (code blocks) — they render inside a
+   `.expressive-code` wrapper and must not be center-aligned. */
+.sl-markdown-content figure:not(.expressive-code figure) {
   margin: 1.5em 0;
   text-align: center;
 }