docs: fix broken and placeholder links (#4097)

* docs: fix broken and placeholder links

Fix the two links called out in #4094 plus one more found while scanning
all docs: the NOTE:addlinktoLOC placeholder in async.mdx now points at
_aggregate_action_queues in robot_client.py; the dead
#mapping-videoencoderconfig--ffmpeg-options anchor in
video_encoding_parameters.mdx now points at get_codec_options in
video.py; and the stale ./cameras#setup-cameras fragment in il_robots.mdx
is dropped to link the cameras guide page.

Closes #4094.

* docs: apply prettier formatting to the video-encoding parameter table

Re-align the Markdown table columns with prettier (v3.6.2, --prose-wrap=preserve)
so the pre-commit 'Format Markdown with Prettier' hook passes. Whitespace only.

docs/source/il_robots.mdx

@@ -98,7 +98,7 @@ The teleoperate command will automatically:
 
 ## Cameras
 
-To add cameras to your setup, follow this [Guide](./cameras#setup-cameras).
+To add cameras to your setup, follow this [Guide](./cameras).
 
 ## Teleoperate with cameras