Add ESLint rules for type safety and fix violations

- Add @typescript-eslint/no-floating-promises: error
- Add @typescript-eslint/no-non-null-assertion: error
- Add @typescript-eslint/prefer-nullish-coalescing: error
- Change @typescript-eslint/no-explicit-any from off to error

Fixes:
- Fix floating promise in NotebookPicker constructor by adding .catch()
- Fix non-null assertion in NotebookPicker.onAfterAttach with null check
- Fix prefer-nullish-coalescing in handler.ts by using ?? instead of ||
- Add inline eslint-disable comments for legitimate any usage in handler.ts

Author: devin-ai-integration[bot]

package.json

@@ -161,9 +161,12 @@
                     "args": "none"
                 }
             ],
-            "@typescript-eslint/no-explicit-any": "off",
+            "@typescript-eslint/no-explicit-any": "error",
             "@typescript-eslint/no-namespace": "off",
             "@typescript-eslint/no-use-before-define": "off",
+            "@typescript-eslint/no-floating-promises": "error",
+            "@typescript-eslint/no-non-null-assertion": "error",
+            "@typescript-eslint/prefer-nullish-coalescing": "error",
             "@typescript-eslint/quotes": [
                 "error",
                 "single",

src/components/NotebookPicker.tsx

@@ -12,18 +12,23 @@ export class NotebookPicker extends ReactWidget {
   constructor(private panel: NotebookPanel) {
     super();
 
-    void panel.context.ready.then(() => {
-      const deepnoteMetadata = this.panel.context.model.getMetadata('deepnote');
-      const metadataNames = deepnoteMetadata?.notebook_names;
-      const names =
-        Array.isArray(metadataNames) &&
-        metadataNames.every(n => typeof n === 'string')
-          ? metadataNames
-          : [];
+    panel.context.ready
+      .then(() => {
+        const deepnoteMetadata =
+          this.panel.context.model.getMetadata('deepnote');
+        const metadataNames = deepnoteMetadata?.notebook_names;
+        const names =
+          Array.isArray(metadataNames) &&
+          metadataNames.every(n => typeof n === 'string')
+            ? metadataNames
+            : [];
 
-      this.selected = names.length === 0 ? null : (names[0] ?? null);
-      this.update();
-    });
+        this.selected = names.length === 0 ? null : (names[0] ?? null);
+        this.update();
+      })
+      .catch(error => {
+        console.error('Failed to initialize NotebookPicker:', error);
+      });
   }
 
   private handleChange = (event: React.ChangeEvent<HTMLSelectElement>) => {
@@ -68,7 +73,9 @@ export class NotebookPicker extends ReactWidget {
   protected onAfterAttach(msg: Message): void {
     super.onAfterAttach(msg);
     requestAnimationFrame(() => {
-      MessageLoop.sendMessage(this.parent!, Widget.ResizeMessage.UnknownSize);
+      if (this.parent) {
+        MessageLoop.sendMessage(this.parent, Widget.ResizeMessage.UnknownSize);
+      }
     });
   }
 

src/handler.ts

@@ -25,9 +25,11 @@ export async function requestAPI(
   try {
     response = await ServerConnection.makeRequest(requestUrl, init, settings);
   } catch (error) {
+    // eslint-disable-next-line @typescript-eslint/no-explicit-any
     throw new ServerConnection.NetworkError(error as any);
   }
 
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
   let data: any = await response.text();
 
   if (data.length > 0) {
@@ -39,7 +41,7 @@ export async function requestAPI(
   }
 
   if (!response.ok) {
-    throw new ServerConnection.ResponseError(response, data.message || data);
+    throw new ServerConnection.ResponseError(response, data.message ?? data);
   }
 
   return data;