[codex] Structure empty mobile pairing payload errors - #3372

Files reviewed

• apps/mobile/src/connection//pairing.ts
• apps/mobile/src/features/connection/pairing.test.ts

Analysis

This PR introduces a new PairairQQQrPayloadEmptyError and switches extractPairingUrlFromQrPayload from throwing a bare Error to throwing the tagged error. It checks out against the Effect conventions:

• Imports: import * as Schema from "effect/Schema" uses the correct subpath namespace import, matching the repo-wide pattern for Schema.TaggedErrorClass error declarations.
• Tagged error: The failure is modeled with Schema.TaggedErrorClass and a precise tag (PairingQrPayloadEmptyError), consistent with conventions.
• No redundant fields / no fabricated cause: This is a pure validation/domain error raised when the scanned QR payload is empty. There is no underlying failure and no additional variable context to capture, so the empty fields object {} and the absence of a cause are appropriate — conventions explicitly state pure validation/domain errors created without an underlying failure do not need a cause, and a precise tag need not invent a redundant singleton field.
• Message: The message getter returns a fixed string derived solely from the (static) nature of the error, not from a stringified cause or a stored unstructured message field. The previously caller-visible message is preserved, and the test asserts both the error type and the exact message.
• No discriminator misuse, no switch tables, no standalone shape interfaces, no compatibility shims.

No convention violations introduced or retained in the changed scope.

The agent made no additional tool calls beyond your initial Check Run Agent prompt.

Agent Credits: 36 credits