onboarding: Remove feature flag and old welcome crate (#36110)

Release Notes:

- N/A

---------

Co-authored-by: MrSubidubi <dev@bahn.sh>
Co-authored-by: Anthony <anthony@zed.dev>

docs/src/telemetry.md

@@ -4,7 +4,8 @@ Zed collects anonymous telemetry data to help the team understand how people are
 
 ## Configuring Telemetry Settings
 
-You have full control over what data is sent out by Zed. To enable or disable some or all telemetry types, open your `settings.json` file via {#action zed::OpenSettings}({#kb zed::OpenSettings}) from the command palette.
+You have full control over what data is sent out by Zed.
+To enable or disable some or all telemetry types, open your `settings.json` file via {#action zed::OpenSettings}({#kb zed::OpenSettings}) from the command palette.
 
 Insert and tweak the following:
 
@@ -15,8 +16,6 @@ Insert and tweak the following:
 },
 ```
 
-The telemetry settings can also be configured via the welcome screen, which can be invoked via the {#action workspace::Welcome} action in the command palette.
-
 ## Dataflow
 
 Telemetry is sent from the application to our servers. Data is proxied through our servers to enable us to easily switch analytics services. We currently use: