docs: address review feedback on experimentation guides

[Zaimwa9]

Changes

Follow-up to #7993 — addresses post-merge review from @Holmus.

• Rename "Experimentation (A/B Testing)" → "A/B Testing with Integrations" to disambiguate sidebar
• Add no-cost reassurance, support link, processing-time admonition to warehouse page
• Add SDK availability note and self-managed reassurance to index
• Clarify "cannot be undone", case sensitivity, SRM warning
• Add create-metric screenshot
• Fix broken anchor, double "manually", awkward wording

How did you test this code?

npm run build in docs/ — no broken links, prettier clean.

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Project	Deployment	Actions	Updated (UTC)
docs	Ready	Preview, Comment	Jul 15, 2026 11:50am

2 Skipped Deployments

Project	Deployment	Actions	Updated (UTC)
flagsmith-frontend-preview	Ignored		Jul 15, 2026 11:50am
flagsmith-frontend-staging	Ignored		Jul 15, 2026 11:50am

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: ASSERTIVE

Plan: Pro Plus

Run ID: 71b10ba8-089a-4a85-85e1-8b0e94cc1d54

📥 Commits

Reviewing files that changed from the base of the PR and between 9e4b1f4 and a4bb22c.

⛔ Files ignored due to path filters (1)

• docs/static/img/experimentation/create-metric-form.png is excluded by !**/*.png

📒 Files selected for processing (7)

• docs/docs/experimentation-ab-testing.md
• docs/docs/experimentation/analyse-an-experiment.md
• docs/docs/experimentation/connect-a-warehouse.md
• docs/docs/experimentation/create-an-experiment.md
• docs/docs/experimentation/create-metrics.md
• docs/docs/experimentation/index.md
• docs/docs/experimentation/run-an-experiment.mdx

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📝 Walkthrough

Walkthrough

Updated experimentation documentation to clarify page naming, environment scope, glossary and SDK availability, metric creation, integrations, warehouse connections, experiment ending, event collection, conversion-event handling, and sample ratio mismatch guidance.

Estimated code review effort: 2 (Simple) | ~10 minutes

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