feat: attach a Pimlico sponsorship policy to every userop

[MayankMittal1]

Summary

• Adds EXPO_PUBLIC_PIMLICO_SPONSORSHIP_POLICY_ID to lib/config.ts.
• useUser passes it as paymasterContext: { sponsorshipPolicyId } to createSmartAccountClient. Every userop goes through this one client, so the policy is sent in every pm_sponsorUserOperation call.
• If the variable is empty, no policy is sent and sponsorship works as it does now.
• Documents the variable in .env.example and the README.

Deploy note

Set EXPO_PUBLIC_PIMLICO_SPONSORSHIP_POLICY_ID=sp_romantic_fallen_one wherever the build env vars live (EAS / web host). It is not set anywhere in the repo, and a build without it silently sends no policy.

Test plan

• tsc --noEmit: no new errors (9 before and after, none in the changed files)
• eslint and prettier pass on the changed files
• With the variable set, send a userop and check that it shows up under the policy in the Pimlico dashboard

🤖 Generated with Claude Code

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2 Skipped Deployments

Project	Deployment	Actions	Updated
solid-app	Ignored	Preview	Sep 24, 2026 5:43pm UTC
solid-app-staging	Ignored		Sep 24, 2026 5:43pm UTC