Chore/cleanup studio deps (#47399)

## Problem

Knip reported some unused dependencies. Some are actually used in
builds, etc but others are not.

## Solution

Remove the really unused dependencies

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

* **Chores**
* Cleaned up unused dependencies and removed some obsolete test/support
files.
* Updated project ignore rules to better match current app structure and
generated files.
* **Bug Fixes**
* No user-facing behavior changed; this release is focused on
maintenance and cleanup.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

knip.jsonc

@@ -9,6 +9,8 @@
     "**/*.test.ts",
     // ignore studio public folder
     "apps/studio/public/**",
+    // ignore studio scripts
+    "apps/studio/scripts/**",
     // ignore studio components that are dynamically imported
     "apps/studio/components/interfaces/ConnectSheet/content/**",
     "apps/studio/components/interfaces/ConnectSheet/ConnectionParameters.tsx",
@@ -16,6 +18,15 @@
     "apps/studio/components/interfaces/ConnectSheet/useMcpUrl.ts",
     // ignore studio data templates
     "apps/studio/data/__templates/**",
+    // ignore studio NextJS to TanStack migration files
+    "apps/studio/compat/**",
+    "apps/studio/routes/**",
+    "apps/studio/router.ts",
+    "apps/studio/start.ts",
+    "apps/studio/routeTree.gen.ts",
+    "apps/studio/styles/fonts.css",
+    // ignore studio evals used in GH action
+    "apps/studio/evals/**",
     // ignore registry blocks in ui-library
     "apps/ui-library/registry/default/**",
     "apps/ui-library/contentlayer.config.js",