fix: Toolbar better auth issue

[benjackwhite]

Problem

When the toolbar gets logged out its super unclear.

Changes

• Adds an authenticate button so its really obvious
• Changes the logic to detect 401 always and trigger the logout
• Removes some old code

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

How did you test this code?

• Manually broke the temporary token locally so that we get the 401 message and validated it worked as expected.

[pauldambra]

[posthog-bot]

📸 UI snapshots have been updated

2 snapshot changes in total. 0 added, 2 modified, 0 deleted:

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

Triggered by this commit.

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[github-actions]

Size Change: +125 B (0%)

Total Size: 824 kB

ℹ️ View Unchanged

Filename	Size	Change
frontend/dist/toolbar.js	824 kB	+125 B (0%)

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