fix(site): update useAgentLogs to make it more testable and add more tests (#19126)

Take 2
Closes https://github.com/coder/internal/issues/644

## Changes made
- Updated how `useAgentLogs` was defined to make it easier to inject
specific data dependencies (basically making the hook more
unit-testable)
- Simplified the hook API to limit the amount of scope of data it needs
to work
- Added more test cases, and re-enabled the one test case we had
previously disabled
- Extracted our mock websocket code into a separate file, and added more
methods to it
- Updated all runtime code to accommodate new changes

.vscode/settings.json

@@ -54,6 +54,7 @@
 		}
 	},
 
+	"tailwindCSS.classFunctions": ["cva", "cn"],
 	"[css][html][markdown][yaml]": {
 		"editor.defaultFormatter": "esbenp.prettier-vscode"
 	},