Debug map and overlay

A wasm stack frame that says lib.ClickField.ClickField.go is already better than wasm-function[412], and it is not yet the .svelte line the author wrote. Compile writes public/__svelte-d/debug-map.json. Printed D carries //# svelte-d-ir orig=lib/ClickField.svelte:1. rewriteStack and rewriteCdpStack join dest D / wasm names back onto that orig. They never invent an orig for a wasm:// frame they cannot join. Async stacks add a tag only: wasm-function[N] [async-wasm] and asyncify_start_unwind [asyncify]. The page hook __svelteDRewriteError rewrites a wrapExportFn throw the same way, and __svelteDLastAwait holds the last .await settlement (failed + reason) so DevTools can see a reject that did not become a D exception.

/__svelte-d/overlay names compile and LDC errors by orig .svelte. /__svelte-d/ir lists printed dests; it is read-only and does not execute. /__svelte-d/wasm-names.json joins the wasm name section onto those dests. Vite serves them as static files from public/. vibe.0 serveStaticFiles serves them too, before the reverse proxy.

packages/svelte-d-kit-admin is the live consumer: Chrome and Firefox consoles, colored vibe.0 logs, optional Puppeteer. The simplified admin example does not require any of that. Learn the IR without a browser first; turn the overlay on when a dest no longer reads as the Svelte you thought you wrote.