docs: update 11-6-stripe.md

[habib424]

Drafted by Ship Ship 🚢 — confidence 🟢 high

What changed

Added a note in the "Payment matching and reconciliation" section explaining that Light uses Stripe's invoice creation date (not the finalization/effective date) when importing invoices, so invoice dates reflect when Stripe created the invoice rather than when it was finalized. This helps customers understand why imported invoice dates may be earlier than expected.

Source PRs

• light#6928 — Use Stripe invoice creation date for imports

How to use this PR

1. Review the diff against the existing article — focus on accuracy and customer voice.
2. Merge if it reads well. Edit and push to this branch if it needs adjustment.
3. Close without merging if the article doesn't actually need this update.

Once we have a track record of clean drafts, we'll graduate to auto-merge with a delay buffer. For now: human-in-the-loop.