VSCE: Change name from "Sourcegraph" to "Search by Sourcegraph" (#51790)

Consistency with #51789 and #51702

This PR changes the name of the other VS Code extension from
"Sourcegraph" to "Search by Sourcegraph" for consistency with he new
Cody naming schema.

The activity bars are now called "Sourcegraph Search" and "Sourcegraph
Cody" (the latter is already called like this in the current release so
this is not a change)

## Test plan



https://github.com/sourcegraph/sourcegraph/assets/458591/84300e12-538c-46e9-afd9-2972608630c4



<!-- All pull requests REQUIRE a test plan:
https://docs.sourcegraph.com/dev/background-information/testing_principles
-->

client/cody/package.json

@@ -77,7 +77,7 @@
       "activitybar": [
         {
           "id": "cody",
-          "title": "Cody",
+          "title": "Sourcegraph Cody",
           "icon": "resources/cody.svg"
         }
       ]

client/vscode/CHANGELOG.md

@@ -6,6 +6,8 @@ The Sourcegraph extension uses major.EVEN_NUMBER.patch (eg. 2.0.1) for release v
 
 ### Changes
 
+- Change the extension name from "Sourcegraph" to "Search by Sourcegraph" [pull/51790](https://github.com/sourcegraph/sourcegraph/pull/51790)
+
 ### Fixes
 
 - Various UI fixes for dark and light themes [pull/50598](https://github.com/sourcegraph/sourcegraph/pull/50598)

client/vscode/README.md

@@ -12,6 +12,8 @@ Sourcegraph’s Code Intelligence feature provides fast, cross-repository naviga
 
 You can read more about Sourcegraph on our [website](https://about.sourcegraph.com/).
 
+Not the extension you're looking for? Download our [Cody AI extension](https://marketplace.visualstudio.com/items?itemName=sourcegraph.cody-ai).
+
 ## Installation
 
 ### From the Visual Studio Marketplace:

client/vscode/package.json

@@ -1,9 +1,9 @@
 {
   "private": true,
   "name": "@sourcegraph/vscode",
-  "displayName": "Sourcegraph",
+  "displayName": "Search by Sourcegraph",
   "version": "2.2.15",
-  "description": "Sourcegraph for VS Code",
+  "description": "Search all of your repositories across all branches and all code hosts",
   "publisher": "sourcegraph",
   "sideEffects": true,
   "license": "Apache-2.0",
@@ -74,7 +74,7 @@
       "activitybar": [
         {
           "id": "sourcegraph-view",
-          "title": "Sourcegraph",
+          "title": "Sourcegraph Search",
           "icon": "images/logomark_dark.svg"
         }
       ]