*: implement share button, improve padding
This commit introduces a share button to the `TimelinePostActionsView`. This button allows users to share a Bluesky post using the standard Android share sheet. The post's URI is passed as text to the share intent.
Additionally, this commit updates the padding for images displayed in `SkeetRowView`. The padding value has been increased from `4.dp` to `12.dp` for a more visually appealing layout.