feat: Fix up batch export addon requirement

[benjackwhite]

Problem

2 things this PR is trying to solve:

1. A staff user can't setup our special http export without the pipelines addon which is annoying
2. We only do frontend checks for the addon which is not good

Changes

• Adds a new button if impersonating to allow bypassing the UI restrictions
• Fixed up the http endpoints for batch exports to validate the addon unless impersonated

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Does this work well for both Cloud and self-hosted?

How did you test this code?

[github-actions]

Size Change: 0 B

Total Size: 1.11 MB

ℹ️ View Unchanged

Filename	Size
frontend/dist/toolbar.js	1.11 MB

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[posthog-bot]

📸 UI snapshots have been updated

4 snapshot changes in total. 0 added, 4 modified, 0 deleted:

• chromium: 0 added, 4 modified, 0 deleted (diff for shard 1, diff for shard 2)
• webkit: 0 added, 0 modified, 0 deleted

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