Service worker and offline behaviour

[codebestia]

Write apps/web/docs/concepts-service-worker.md for sw.js: registration lifecycle, the content-free push handler, notification click routing, update/skip-waiting behaviour, and what the app does offline.

Acceptance criteria:

• Documents registration, activation and the update path, including how a stale worker is replaced
• Documents the push handler and confirms payloads are content-free by design, cross-linking the backend push docs
• Documents click-to-route behaviour, including focusing an existing tab rather than opening a duplicate
• States plainly what does and does not work offline today

[Essence-3]

@Essence-3 has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hi, I have a solution to this issue and I would love to work on it.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Essence-3 to this issue.

[G-ELM]

@G-ELM has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hello
I can work on this.
Please assign.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @G-ELM to this issue.

[drips-wave]

Congratulations, @G-ELM! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on August 31, 2026.

🧑‍💻 @G-ELM: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

Warning

When opening a PR, please link it to this issue to ensure it gets tracked accurately. Points are awarded when this issue is marked as completed by the maintainer.

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