VSCode extension fails to build (broken since 2025-11-02)

[jrosskopf]

Summary

The VSCode extension (cli/vscode-extension/) does not compile. npm run build (webpack) and npx tsc --noEmit both fail. The breakage is committed and traces to the last extension commit fcebf3a ("First draft of write support", 2025-11-02), so the extension has been unshippable for ~7 months.

Root causes

1. @flapi/shared is never built. Its package.json types points to dist/index.d.ts, but cli/shared/dist/ does not exist after npm ci (no prepare script). The extension then resolves a stale/missing type and reports TS2339: Property 'operation' does not exist on type 'EndpointConfig' (src/providers/endpointsProvider.ts:60,61,79,80) — even though operation? is declared in shared/src/lib/types.ts:52.
2. Malformed template literals. src/webview/endpointTesterPanel.ts:1942-1966 (the new renderWriteOperationResponse write-support block) uses raw backticks and ${...} inside the surrounding webview HTML template literal, instead of the escaped \`` / ${ form used everywhere else (e.g. lines 1897, 1920, 2030). This prematurely terminates the outer literal and desyncs the parser (TS1005/TS1110/TS1127`).

Fix

• Add a prepare (build) step so @flapi/shared dist/ is always present.
• Escape the nested template literals in the write-support block.

Verify

cd cli/shared && npm run build then cd ../vscode-extension && npm ci && npm run build && npx tsc --noEmit — all succeed.

Found by docs/CLIENT_PARITY_AUDIT.md (P0).