[codex] Structure Electron protocol teardown failures

[juliusmarminge]

Summary

• preserve the protocol scheme and exact underlying cause for scoped Electron protocol unregistration failures
• keep registration failures typed while surfacing teardown failures as structured finalizer defects
• construct errors directly and make registration/unregistration messages derive from structured fields
• cover both registration and scoped unregistration cause preservation

Validation

• vp test apps/desktop/src/electron/ElectronProtocol.test.ts
• vp check
• vp run typecheck

Overlap audit

• apps/desktop/src/electron/ElectronProtocol.ts also appears in unrelated local-auth startup PR fix: stabilize local dev auth startup #3252; no active error-audit PR touches this module.

Note

Structure Electron protocol teardown failures into typed errors

• Adds ElectronProtocolUnregistrationError to capture failures from Electron.protocol.unhandle, preserving the scheme and original cause.
• Updates the acquireRelease teardown in registerDesktopProtocol to use Effect.try instead of Effect.sync, wrapping thrown exceptions in the new error type and terminating via orDie.
• Updates ElectronProtocolRegistrationError message format to Failed to register Electron protocol scheme "<scheme>".
• Adds tests verifying error class, scheme, cause, and message for both registration and unregistration failures.

^{Macroscope summarized dda508c.}

[macroscopeapp]

Approvability

Verdict: Approved

Straightforward error handling improvement that wraps protocol unregistration failures in a structured error class, matching the existing pattern for registration errors. The change is self-contained with good test coverage and minimal runtime impact.

^{You can customize Macroscope's approvability policy. Learn more.}