Feat: Fixed option for control after/before generate (#7517)

Followup to #7510.
- Makes `Fixed` a full option with description and swaps to radio
buttons
- Sorts the options to be the same order as litegraph
- Removes the "Edit control settings" button

| Before | After |
| ------ | ----- |
| <img width="360" alt="before"
src="https://github.com/user-attachments/assets/e0e4acda-ba02-4a25-aeca-dd7f1adea0fb"
/>| <img width="360" alt="after"
src="https://github.com/user-attachments/assets/5c4c0fbf-a949-4ce1-83e9-5acdeac3b81a"
/>|

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-7517-Austin-vue-fixed-2ca6d73d3650817ca845fb948bee73ac)
by [Unito](https://www.unito.io)

src/locales/en/main.json

@@ -2073,6 +2073,8 @@
       "incrementDesc": "Adds 1 to the value number",
       "decrement": "Decrement Value",
       "decrementDesc": "Subtracts 1 from the value number",
+      "fixed": "Fixed Value",
+      "fixedDesc": "Leaves value unchanged",
       "editSettings": "Edit control settings"
     }
   },