telemetry(amazonq): add vectorIndexEnabled boolean to workspace index telemetry (aws#6720)

## Problem
We do not know the % of users who has vector index enabled.

## Solution
Add a boolean flag for whether  vector index is enabled.

---

- Treat all work as PUBLIC. Private `feature/x` branches will not be
squash-merged at release time.
- Your code changes must meet the guidelines in
[CONTRIBUTING.md](https://github.com/aws/aws-toolkit-vscode/blob/master/CONTRIBUTING.md#guidelines).
- License: I confirm that my contribution is made under the terms of the
Apache 2.0 license.

Author: leigaol

packages/core/src/amazonq/lsp/lspController.ts

@@ -357,6 +357,7 @@ export class LspController {
                     amazonqIndexMemoryUsageInMB: usage ? usage.memoryUsage / (1024 * 1024) : undefined,
                     amazonqIndexCpuUsagePercentage: usage ? usage.cpuUsage : undefined,
                     amazonqIndexFileSizeInMB: totalSizeBytes / (1024 * 1024),
+                    amazonqVectorIndexEnabled: buildIndexConfig.isVectorIndexEnabled,
                     credentialStartUrl: buildIndexConfig.startUrl,
                 })
             } else {
@@ -366,6 +367,7 @@ export class LspController {
                     result: 'Failed',
                     amazonqIndexFileCount: 0,
                     amazonqIndexFileSizeInMB: 0,
+                    amazonqVectorIndexEnabled: buildIndexConfig.isVectorIndexEnabled,
                     reason: `Unknown`,
                 })
             }
@@ -377,6 +379,7 @@ export class LspController {
                 result: 'Failed',
                 amazonqIndexFileCount: 0,
                 amazonqIndexFileSizeInMB: 0,
+                amazonqVectorIndexEnabled: buildIndexConfig.isVectorIndexEnabled,
                 reason: `${error instanceof Error ? error.name : 'Unknown'}`,
                 reasonDesc: `Error when building index. ${error instanceof Error ? error.message : error}`,
             })

packages/core/src/shared/telemetry/vscodeTelemetry.json

@@ -52,6 +52,11 @@
             "type": "int",
             "description": "The sum of file sizes that were indexed in MB"
         },
+        {
+            "name": "amazonqVectorIndexEnabled",
+            "type": "boolean",
+            "description": "True if vector index is enabled"
+        },
         {
             "name": "amazonqIndexFileCount",
             "type": "int",
@@ -624,6 +629,10 @@
                 {
                     "type": "credentialStartUrl",
                     "required": false
+                },
+                {
+                    "type": "amazonqVectorIndexEnabled",
+                    "required": false
                 }
             ]
         },