Add Base Verify Onchain demo link

[kushagras481]

Summary

Add a link to the hosted Base Verify Onchain demo from the Apps guide so developers can try the flow directly.

What changed

• Updated the Verify Users Onchain guide tip to link to https://verify.base.dev/onchain-demo

Test plan

• Confirmed the docs diff only updates the demo link copy

Linear: N/A

type=routine
risk=low
impact=sev5
backwards_compatible=true
automerge=false

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Project	Status	Preview	Updated (UTC)
base	🟢 Ready	View Preview	Aug 4, 2026, 4:32 PM

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[cb-heimdall]

✅ Heimdall Review Status

Requirement	Status	More Info
Reviews	✅ 1/1	Denominator calculation Show calculation 1 if user is bot 0 1 if user is external 0 2 if repo is sensitive 0 From .codeflow.yml 1 Additional review requirements Show calculation Max 0 0 From CODEOWNERS 0 Global minimum 0 Max 1 1 1 if commit is unverified 0 Sum 1