fix(web): wait for focused Passkey unlock

[eminogrande]

Summary

• stop automatically polling Connect and invoking WebAuthn during the return-page effect
• present an explicit Use Passkey & Open Chat action after an exact tab-bound Connect return
• preserve the existing manual resume action for pending sessions opened without the return nonce

Why

Safari/WebKit can reject the second PRF assertion with not focused when it starts automatically immediately after returning from Connect. The explicit click provides a focused user activation before WebAuthn.

Verification

• pnpm --dir web check
• pnpm --dir web typecheck
• pnpm --dir web test:unit — 9 passed
• pnpm --dir web build
• pnpm --dir web test:e2e:smoke — 7 passed

Part of #3. This PR does not include multi-Space work or domain/relay migration.

[eminogrande]

Superseded by #12 — the same WebAuthn focus wait is now on main (features/nuri-wallet/lib/webauthn.ts, whenDocumentFocused). Two of us hit and fixed this bug independently, which is recorded in the handover doc as the reason that document exists.

The e2e test in this PR is still worth having — it has no equivalent on main. Suggest cherry-picking just web/tests/e2e/smoke.spec.ts and closing the rest.

[taner-caliskan]

Exact-head review of 86b37749ce46f2a19b4294624f995b3587c71206. Current-head Desktop Build (macOS) is failing. This is material for focused passkey unlock across web/desktop boundaries. Fix or conclusively classify it, rerun green, and verify focus loss/return, cancellation, duplicate prompts and successful unlock.