docs: Mintlify MDX docs + docs.json; bump Speakeasy to 1.787.0 (#382)

docs/components/inputunion.mdx

@@ -0,0 +1,21 @@
+---
+title: "InputUnion"
+---
+
+The input to the generation — either a prompt string or an array of messages
+
+
+## Supported Types
+
+### `components.Input1`
+
+```python
+value: components.Input1 = /* values here */
+```
+
+### `components.Input2`
+
+```python
+value: components.Input2 = /* values here */
+```
+