Remove visible 'TBD' from docs (#17979)

Release Notes:

- N/A

docs/src/extensions/languages.md

@@ -284,7 +284,9 @@ The `@run` capture specifies where the run button should appear in the editor. O
 | @run    | Captures the script name                               |
 | @script | Also captures the script name (for different purposes) |
 
+<!--
 TBD: `#set! tag`
+-->
 
 ## Language Servers
 

docs/src/key-bindings.md

@@ -177,8 +177,10 @@ See the [tasks documentation](tasks.md#custom-keybindings-for-tasks) for more.
 
 #### Global
 
+<!--
 TBD: Update these to reflect current bindings
 TBD: Add Column with Linux shortcuts
+-->
 
 | **Command**               | **Target**   | **Default Shortcut**    |
 | ------------------------- | ------------ | ----------------------- |

docs/src/languages/javascript.md

@@ -26,6 +26,7 @@ For example, if you have Prettier installed and on your `PATH`, you can use it t
 }
 ```
 
+<!--
 ## JSX
 
 TBD: Mention JSX
@@ -35,6 +36,7 @@ TBD: Mention JSX
 TBD: Document JSDoc support in Zed.
 
 - Tree Sitter: [tree-sitter/tree-sitter-jsdoc](https://github.com/tree-sitter/tree-sitter-jsdoc)
+-->
 
 ## ESLint