docs: add non-OTEL Sentry setup option

[Lotte-Verheyden]

Summary

• Adds Option A: Use Sentry without OpenTelemetry as the simplest approach for users who don't need Sentry's performance tracing alongside Langfuse. Covers both JS/TS (skipOpenTelemetrySetup: true) and Python (sentry_sdk v2.x native instrumentation).
• Renumbers existing Shared TracerProvider and Isolated TracerProvider options to B and C, updates all cross-references.
• Updates the "Why" section to mention Python SDK v3+ also uses OTEL.

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Project	Deployment	Actions	Updated (UTC)
langfuse-docs	Ready	Preview, Comment	Mar 19, 2026 6:14pm

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📦 Next.js Bundle Analysis for langfuse-docs

This analysis was generated by the Next.js Bundle Analysis action. 🤖

One Page Changed Size

The following page changed size from the code in this PR compared to its base branch:

Page	Size (compressed)	First Load	% of Budget (350 KB)
/faq/all/existing-sentry-setup	64.9 KB	476.24 KB	136.07% (🟡 +0.15%)

Details

Only the gzipped size is provided here based on an expert tip.

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