[BUG] `TypeError: Cannot redefine property: name` when using esbuild with `keepNames: true`, preventing VSCode extension telemetry from being sent

**Description/Screenshot**

Discovered from https://github.com/microsoft/vscode-containers/issues/367 originally. Related issues:
- https://github.com/microsoft/vscode-extension-telemetry/issues/237
- https://github.com/microsoft/vscode-extension-telemetry/issues/150
- This repo: #2523
- This repo: #2643

Quoting my original issue here, but please look there for the most up-to-date:

> Boring analysis: the reason it was happening was because we're using `keepNames` in esbuild, to make it not mangle class/function names (which we need if we want useful call stacks). Esbuild writes code into the bundle that, at load time (which is run time), tries to set the `name` property on the minified classes/functions to the original name.
>
> Some of the AppInsights packages are freezing some of their stuff, which makes it impossible to set the `name` property. The error that was thrown (and then caught and eaten) would resemble:
>
> ```
> TypeError: Cannot redefine property: name
> at defineProperty ()
> at __name (d:\\vscode-containers\\dist\\extension.bundle.js:8:33)
> at node_modules/@microsoft/1ds-core-js/dist-es5/AppInsightsCore.js (d:\\vscode-containers\\dist\\extension.bundle.js:16157:5)
> at __init (d:\\vscode-containers\\dist\\extension.bundle.js:10:56)
> at node_modules/@microsoft/1ds-core-js/dist-es5/Index.js (d:\\vscode-containers\\dist\\extension.bundle.js:16819:5)
> at __init (d:\\vscode-containers\\dist\\extension.bundle.js:10:56)
> at d:\\vscode-containers\\dist\\extension.bundle.js:20303:57
> at async getAICore (d:\\vscode-containers\\dist\\extension.bundle.js:20303:21)
> at async oneDataSystemClientFactory (d:\\vscode-containers\\dist\\extension.bundle.js:20343:29)
> ```
>
> The end result was that loading the AppInsights packages failed silently, and the AppInsights reporter never got built--so when we logged telemetry events, they were just screamed into the void.
>
> I considered three options. The first was to build the extension as ESM, but unfortunately this just didn't work at all.
>
> The second was to turn off `keepNames`...but that would negatively impact both telemetry and the issue reporter by giving us mangled names that we would have to translate after-the-fact if we wanted to investigate.
>
> The third was Opus' idea (nice job AI!). Basically, we build the `@vscode/extension-telemetry` package into its own bundle, with `keepNames` off, and then build everything else (extension and other dependencies) into the main bundle, with an alias to rewrite imports to `@vscode/extension-telemetry` to point to the other bundle.

**Steps to Reproduce**
1. Clone and `npm install` from https://github.com/microsoft/vscode-containers/tree/v2.4.0
2. In launch.json, change `DEBUGTELEMETRY` env var to 0
3. F5 and do anything in the Container Tools extension

- OS/Browser: Any OS
- SDK Version [e.g. 22]: (Below)
- How you initialized the SDK:
`@vscode/extension-telemetry@0.9.9`
`@microsoft/1ds-core-js@4.3.10`
`@microsoft/1ds-post-js@4.3.10`
`@microsoft/applicationinsights-web-basic@3.3.10`

**Expected behavior**
Works with ESBuild without issues

Reproduce the failure using the linked vscode-containers v2.4.0 steps and inspect the esbuild configuration involving keepNames and the listed telemetry packages. Trace how @vscode/extension-telemetry is bundled and loaded; done means the Cannot redefine property: name error no longer prevents the AppInsights reporter from being built and telemetry events are sent.

Written by the indexing model from the issue text.