Use InfluxDB v3 API for analytics reporting

[SMillerDev]

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This makes sure we're using the most modern API to write analytics data. Just to keep up to date.

TODO:

• Change URL to the new brew.sh endpoint
• Remove authorization header because it has a fallback with the new endpoint, can also be a followup

[Copilot]

Pull request overview

Updates Homebrew’s analytics reporting to use the InfluxDB v3 line-protocol write endpoint in Utils::Analytics, aligning the client with a newer ingestion API.

Changes:

• Switch analytics write URL from /api/v2/write to /api/v3/write_lp with updated query parameters.

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[SMillerDev]

Split it out to: #23639

[MikeMcQuaid]

Same deal: Thanks! Can you confirm you've run this locally with export HOMEBREW_ANALYTICS_DEBUG=1 and it produces identical output (bar the URL) to the previous approach?

[SMillerDev]

The analytics still works fine and has identical output. I will wait with the merge until after the next release though, to make sure we don't change too much in one go.