Runtime diagnostics

Contract

v0.1.8 adds diagnostics for the small Go WebAssembly frontend runtime from v0.1.7. Diagnostics report framework failures without defining a logging transport.

The runtime returns mount errors directly from Mount. After mount, callback panics and render failures are reported through an optional Go function:

type Options struct {
	OnError func(error)
}

If OnError is nil, the runtime writes a redacted message to the browser console. Application code may call its own logger from OnError.

Framework diagnostics must not contain tokens, cookies, raw provider payloads, stack traces with customer data, SQL, private customer data, or credential headers. Product modules own product error copy and product logging.

Consequence

Core reports mount, render, and callback-wrapper failures consistently without owning application logging.