Fix Typo, Improve Readability, and Enhance Token Extension Handling (#471)

**This pull request includes the following changes:**

- Fixed a typo: Corrected "procesisg" to "processing" in test
descriptions.
- Improved readability: Adjusted comment formatting in
parseFeatureAccount.ts.
- Enhanced token extension handling: Updated unparseableExtension naming
for consistency in token-extension.ts.

These changes improve code clarity, maintainability, and ensure better
developer experience.
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> [!IMPORTANT]
> Fixes typos, improves readability, and renames `unparseableExtension`
to `unparsableExtension` for consistency.
> 
>   - **Token Extension Handling**:
> - Renamed `unparseableExtension` to `unparsableExtension` in
`token-extension.ts` for consistency.
>   - **Typo Fixes**:
>     - Corrected "procesisg" to "processing" in `endpoint.test.ts`.
>     - Corrected "unkonwn" to "unknown" in `anchor.tsx`.
>   - **Readability Improvements**:
>     - Adjusted comment formatting in `parseFeatureAccount.ts`.
> 
> <sup>This description was created by </sup>[<img alt="Ellipsis"
src="https://img.shields.io/badge/Ellipsis-blue?color=175173">](https://www.ellipsis.dev?ref=solana-foundation%2Fexplorer&utm_source=github&utm_medium=referral)<sup>
for 9e195d3. It will automatically
update as commits are pushed.</sup>

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---------

Co-authored-by: Noah Gundotra <ngundotra@users.noreply.github.com>

Author: kilavvy

app/api/metadata/proxy/__tests__/endpoint.test.ts

@@ -72,7 +72,7 @@ describe('metadata/[network] endpoint', () => {
         expect(response.status).toBe(400);
     });
 
-    it('should return proper status upon processig data', async () => {
+    it('should return proper status upon processing data', async () => {
         setEnvironment('NEXT_PUBLIC_METADATA_ENABLED', 'true');
 
         const { request, nextParams } = requestFactory();

app/utils/anchor.tsx

@@ -503,6 +503,6 @@ function typeDisplayName(
             if ('option' in type) return `${typeDisplayName(type.option)} (optional)`;
             if ('vec' in type) return `${typeDisplayName(type.vec)}[]`;
             if ('array' in type) return `${typeDisplayName(type.array[0])}[${type.array[1]}]`;
-            return 'unkonwn';
+            return 'unknown';
     }
 }

app/utils/parseFeatureAccount.ts

@@ -15,7 +15,7 @@ function isFeatureAccount(account: Account): boolean {
 export const useFeatureAccount = (account: Account) => {
     const isFeature = isFeatureAccount(account);
 
-    // allow to retreive sign of a Feature Account
+    // allow to retrieve sign of a Feature Account
     return { isFeature };
 };