fix(skill): document rich-text align is an object, not a string

Author: dazzatronus

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@shotstack/cli",
-  "version": "0.3.1",
+  "version": "0.3.2",
   "description": "Command-line interface for the Shotstack video rendering API.",
   "license": "Apache-2.0",
   "homepage": "https://github.com/shotstack/shotstack-cli",

shared/agent-core.md

@@ -16,6 +16,7 @@ CSS naming conventions (`alignment`, `vertical: "center"`) **do not** apply. The
 | You'd guess (wrong) | API uses (right) |
 |---|---|
 | `alignment` | `align` |
+| `align: "center"` (string on rich-text asset) | `align: { "horizontal": "center", "vertical": "middle" }` (object) |
 | `align.vertical: "center"` | `align.vertical: "middle"` |
 | `font.name` | `font.family` |
 | `duration` | `length` |