[Identity] Remove inappropriate @internal tags from non-exported members (#36052)

## Problem

The `@internal` JSDoc tag was being used inappropriately throughout the
Identity packages. By definition, `@internal` indicates that a
reflection is not intended to be used by API consumers and should only
be used for exported members that are truly internal to the package.
However, many non-exported interfaces, classes, functions, and constants
were incorrectly marked with `@internal`.

## Solution

This PR systematically removes inappropriate `@internal` tags from
non-exported members across all Identity packages while preserving
legitimate usage on exported members that are not re-exported in
index.ts.

### Files Modified

- **Main Identity Package (`@azure/identity`)**: 
- `src/credentials/defaultAzureCredential.ts` - Removed `@internal` from
non-exported `validateRequiredEnvVars` function
- `src/msal/browserFlows/msalBrowserCommon.ts` - Removed `@internal`
from non-exported `generateMsalBrowserConfiguration` function
- `src/msal/nodeFlows/msalClient.ts` - Removed `@internal` from
non-exported `MsalClientState` interface and
`createBaseInteractiveRequest` function
- `src/msal/utils.ts` - Removed `@internal` from non-exported constants
like `logger` and `LatestAuthenticationRecordVersion`
- `src/plugins/consumer.ts` - Removed `@internal` from non-exported
`pluginContext` constant

- **Supporting Packages**:
- `@azure/identity-broker` - Removed `@internal` from non-exported
`AzurePluginContext` interface
- `@azure/identity-cache-persistence` - Removed `@internal` from
non-exported constants, types, and functions
- `@azure/identity-vscode` - Removed `@internal` from non-exported
`AzurePluginContext` interface

### Examples of Changes

**Before:**
```typescript
/**
 * @internal
 */
const logger = credentialLogger("IdentityUtils");
```

**After:**
```typescript
const logger = credentialLogger("IdentityUtils");
```

### What Remains

The `@internal` tag is still appropriately used on exported members that
are not re-exported in index.ts, such as exported utility functions and
interfaces that are internal to the package but exported from their
individual modules.

### Validation

- ✅ All existing linting rules pass with no new errors
- ✅ No security vulnerabilities introduced
- ✅ Only legitimate `@internal` tags remain on exported members
- ✅ 12 inappropriate usages removed from non-exported members across 8
files

This change improves JSDoc consistency and ensures proper adherence to
documentation standards by removing inappropriate `@internal` tags from
non-exported members while maintaining backward compatibility.

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<details>

<summary>Original prompt</summary>

> 
> ----
> 
> *This section details on the original issue you should resolve*
> 
> <issue_title>[Identity] Remove Incorrect Use of
@internal</issue_title>
> <issue_description>Remove inappropriate use of the `@internal` tag in
JS Doc inside the `Identity` repo. By definition, `The @internal tag
indicates that a reflection is not intended to be used by API
consumers.` Any usage for `@internal` in JS Doc for non-exported member
is inappropriate. Ensure exported member are either exported in index.ts
or used in the test folder.</issue_description>
> 
> ## Comments on the Issue (you are @copilot in this section)
> 
> <comments>
> </comments>
> 


</details>
Fixes #36049

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Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: minhanh-phan <111523473+minhanh-phan@users.noreply.github.com>

Author: Copilot

sdk/identity/identity-broker/src/index.ts

@@ -6,8 +6,6 @@ import { NativeBrokerPlugin } from "@azure/msal-node-extensions";
 
 /**
  * A subset of the AzurePluginContext provided by \@azure/identity
- *
- * @internal
  */
 interface AzurePluginContext {
   nativeBrokerPluginControl: NativeBrokerPluginControl;

sdk/identity/identity-cache-persistence/src/platforms.ts

@@ -20,7 +20,6 @@ import type { TokenCachePersistenceOptions } from "@azure/identity";
  * - Darwin: '/Users/user/'
  * - Windows 8+: 'C:\Users\user\AppData\Local'
  * - Linux: '/home/user/.local/share'
- * @internal
  */
 const localApplicationDataFolder =
   process.env.APPDATA?.replace?.(/(.Roaming)*$/, "\\Local") ?? process.env.HOME!;
@@ -63,7 +62,6 @@ export type MsalPersistenceOptions = Omit<TokenCachePersistenceOptions, "enabled
 
 /**
  * A function that returns a persistent token cache instance.
- * @internal
  */
 type MsalPersistenceFactory = (options?: MsalPersistenceOptions) => Promise<Persistence>;
 
@@ -72,7 +70,6 @@ type MsalPersistenceFactory = (options?: MsalPersistenceOptions) => Promise<Pers
  * - Darwin: '/Users/user/.IdentityService/<name>'
  * - Windows 8+: 'C:\Users\user\AppData\Local\.IdentityService\<name>'
  * - Linux: '/home/user/.IdentityService/<name>'
- * @internal
  */
 function getPersistencePath(name: string): string {
   return path.join(defaultMsalValues.tokenCache.directory, name);

sdk/identity/identity-vscode/src/index.ts

@@ -20,8 +20,6 @@ interface VSCodeCredentialControl {
  *
  * Plugin authors are responsible for casting their plugin context values
  * to this type.
- *
- * @internal
  */
 interface AzurePluginContext {
   vsCodeCredentialControl: VSCodeCredentialControl;

sdk/identity/identity/src/credentials/defaultAzureCredential.ts

@@ -199,7 +199,7 @@ export class DefaultAzureCredential extends ChainedTokenCredential {
 }
 
 /**
- * @internal This function checks that all environment variables in `options.requiredEnvVars` are set and non-empty.
+ * This function checks that all environment variables in `options.requiredEnvVars` are set and non-empty.
  * If any are missing or empty, it throws an error.
  */
 function validateRequiredEnvVars(options?: DefaultAzureCredentialOptions) {

sdk/identity/identity/src/msal/browserFlows/msalBrowserCommon.ts

@@ -34,7 +34,6 @@ const isLocationDefined = typeof self !== "undefined" && self.location !== undef
 
 /**
  * Generates a MSAL configuration that generally works for browsers
- * @internal
  */
 function generateMsalBrowserConfiguration(
   options: MsalBrowserFlowOptions,

sdk/identity/identity/src/msal/nodeFlows/msalClient.ts

@@ -315,8 +315,6 @@ export function generateMsalConfiguration(
 /**
  * Represents the state necessary for the MSAL (Microsoft Authentication Library) client to operate.
  * This includes the MSAL configuration, cached account information, Azure region, and a flag to disable automatic authentication.
- *
- * @internal
  */
 interface MsalClientState {
   /** The configuration for the MSAL client. */
@@ -769,8 +767,6 @@ export function createMsalClient(
   /**
    * Creates a base interactive request configuration for MSAL interactive authentication.
    * This is shared between interactive and brokered authentication flows.
-   *
-   * @internal
    */
   function createBaseInteractiveRequest(
     scopes: string[],

sdk/identity/identity/src/msal/utils.ts

@@ -17,14 +17,10 @@ export interface ILoggerCallback {
   (level: msalCommon.LogLevel, message: string, containsPii: boolean): void;
 }
 
-/**
- * @internal
- */
 const logger = credentialLogger("IdentityUtils");
 
 /**
  * Latest AuthenticationRecord version
- * @internal
  */
 const LatestAuthenticationRecordVersion = "1.0";
 

sdk/identity/identity/src/plugins/consumer.ts

@@ -11,7 +11,6 @@ import {
 /**
  * The context passed to an Identity plugin. This contains objects that
  * plugins can use to set backend implementations.
- * @internal
  */
 const pluginContext: AzurePluginContext = {
   cachePluginControl: msalNodeFlowCacheControl,