fix: address all seven final-gate findings for typed api blocks

B1: qualify each generated __wrn_api_check_* assertion name with a short
hash of the page's path (relative to app/, for reproducibility across
checkouts) so two pages declaring a same-named block no longer collide
with an identical type alias (TS2300).

B2: skip assertion emission for any block that is not client-mode, or
that has zero declared request fields. ssr sectioned blocks can never
declare a request and always fell back to Record<string, never>, whose
keyof is `string` -- making the key-exactness arm of AssertAssignable
evaluate to false unconditionally (TS2344) on every ssr sectioned block
regardless of correctness. Chose to skip both non-client blocks and
zero-field client blocks, since neither has anything meaningful to
assert type-safety about.

B3: only resolve the endpoint's input (query params / ctx.req.json())
when the endpoint declares an input schema. Previously the router-set
fix accidentally read the request body unconditionally, so a handler
with no input schema that parses the request itself hit
ERR_BODY_ALREADY_USED.

B4: run response/error bodies in client-mode api blocks through
eraseFunctionTypes, matching every other browser-bound body in
client-codegen.ts, so a TypeScript-only construct inside one (e.g. an
annotated locally-declared function) doesn't reach the .mjs artifact.

B5: only exclude "api" from state/prop destructuring in the generated
browser module when the page actually has client-mode api blocks (i.e.
there is a real `api` binding to shadow). Previously "api" was always
excluded, so a page with `state api` and no api blocks got an
undeclared `api` reference (ReferenceError) in client code.

B6: prefix each emitted assertion with `export`, so it isn't flagged as
an unused local under a downstream project's noUnusedLocals (TS6196).

B7: wrnexusCallApi now resolves with undefined for an ok 204/205
response, or an ok response with an empty/unparseable body, instead of
rejecting with "Response was not valid JSON" -- matching the spec's
failure table (error path only for non-2xx, network failure, or an
actually unparseable body on a non-empty response).

Regenerated examples/basic-app's generated types and editor bundles to
match. Confirmed the example's type gate still fails when an
unaccepted field is added to a request body, and passes cleanly
otherwise.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

packages/core/src/endpoint.ts

@@ -101,13 +101,16 @@ export function defineEndpoint(
       // (unit tests, internal RPC-style calls) may still pass one explicitly, and
       // that always wins. Otherwise, read the request ourselves: query params for
       // GET/HEAD, JSON body for everything else.
-      const resolvedInput =
-        rawInput !== undefined
-          ? rawInput
-          : ctx.req.method.toUpperCase() === "GET" || ctx.req.method.toUpperCase() === "HEAD"
-            ? Object.fromEntries(ctx.url.searchParams)
-            : await ctx.req.json().catch(() => ({}));
-      const input = definition.input ? schemaValue(definition.input, resolvedInput) : resolvedInput;
+      let input: unknown = rawInput;
+      if (definition.input) {
+        const resolvedInput =
+          rawInput !== undefined
+            ? rawInput
+            : ctx.req.method.toUpperCase() === "GET" || ctx.req.method.toUpperCase() === "HEAD"
+              ? Object.fromEntries(ctx.url.searchParams)
+              : await ctx.req.json().catch(() => ({}));
+        input = schemaValue(definition.input, resolvedInput);
+      }
       const rawOutput = await definition.handler(input, ctx);
       const output = definition.output ? schemaValue(definition.output, rawOutput) : rawOutput;
       return output instanceof Response ? output : json({ data: output });