refactor: remove dead _routeName param, eliminate two ! non-null assertions

- with-timing: drop unused `_routeName` parameter from withTiming() and
  all test call sites; the path is taken from the live request URL and
  normalized later in computeApiStats — the explicit name was dead weight
- log-reader: extract `entries[i].cacheStats` to a temp variable so
  TypeScript can narrow the type; removes the `!` assertion
- retrospective: destructure `opts.sessionId` before use in filter
  callback; removes the `!` assertion on an optional-chained value

No behaviour change — all 508 core tests and 413 passing web tests green.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/core/src/log-reader.ts

@@ -261,8 +261,9 @@ export function computeApiStats(entries: ApiLogEntry[]): ApiPerfResult {
 
   let latestCacheStats: ApiLogEntry["cacheStats"] | null = null;
   for (let i = entries.length - 1; i >= 0; i--) {
-    if (entries[i].cacheStats) {
-      latestCacheStats = entries[i].cacheStats!;
+    const stats = entries[i].cacheStats;
+    if (stats) {
+      latestCacheStats = stats;
       break;
     }
   }

packages/core/src/retrospective.ts

@@ -113,8 +113,9 @@ export function loadRetrospectives(
   }
 
   // Filter by session ID — match exact session followed by timestamp delimiter
-  if (opts?.sessionId) {
-    files = files.filter((f) => f.startsWith(`${opts.sessionId!}-`));
+  const sessionIdFilter = opts?.sessionId;
+  if (sessionIdFilter) {
+    files = files.filter((f) => f.startsWith(`${sessionIdFilter}-`));
   }
 
   const results: Retrospective[] = [];

packages/web/src/lib/__tests__/with-timing.test.ts

@@ -28,7 +28,7 @@ describe("withTiming", () => {
       new Response(JSON.stringify({ ok: true }), { status: 200 }),
     );
 
-    const wrapped = withTiming(innerHandler, "test-route");
+    const wrapped = withTiming(innerHandler);
     const req = new Request("http://localhost:3000/api/sessions");
     await wrapped(req);
 
@@ -42,7 +42,7 @@ describe("withTiming", () => {
     );
     const ctx = { params: { id: "abc" } };
 
-    const wrapped = withTiming(innerHandler, "test-route");
+    const wrapped = withTiming(innerHandler);
     const req = new Request("http://localhost:3000/api/sessions/abc");
     await wrapped(req, ctx);
 
@@ -57,7 +57,7 @@ describe("withTiming", () => {
     });
     const innerHandler = vi.fn().mockResolvedValue(originalResponse);
 
-    const wrapped = withTiming(innerHandler, "test-route");
+    const wrapped = withTiming(innerHandler);
     const req = new Request("http://localhost:3000/api/sessions");
     const result = await wrapped(req);
 
@@ -70,7 +70,7 @@ describe("withTiming", () => {
       new Response("ok", { status: 200 }),
     );
 
-    const wrapped = withTiming(innerHandler, "test-route");
+    const wrapped = withTiming(innerHandler);
     const req = new Request("http://localhost:3000/api/sessions");
     await wrapped(req);
 
@@ -91,7 +91,7 @@ describe("withTiming", () => {
       new Response("created", { status: 201 }),
     );
 
-    const wrapped = withTiming(innerHandler, "test-route");
+    const wrapped = withTiming(innerHandler);
     const req = new Request("http://localhost:3000/api/spawn", {
       method: "POST",
       body: JSON.stringify({ session: "ao-1" }),
@@ -108,7 +108,7 @@ describe("withTiming", () => {
       new Response("not found", { status: 404 }),
     );
 
-    const wrapped = withTiming(innerHandler, "test-route");
+    const wrapped = withTiming(innerHandler);
     const req = new Request("http://localhost:3000/api/sessions/unknown");
     await wrapped(req);
 
@@ -123,7 +123,7 @@ describe("withTiming", () => {
       new Response("internal error", { status: 500 }),
     );
 
-    const wrapped = withTiming(innerHandler, "test-route");
+    const wrapped = withTiming(innerHandler);
     const req = new Request("http://localhost:3000/api/sessions");
     await wrapped(req);
 
@@ -137,7 +137,7 @@ describe("withTiming", () => {
       new Error("database connection failed"),
     );
 
-    const wrapped = withTiming(innerHandler, "test-route");
+    const wrapped = withTiming(innerHandler);
     const req = new Request("http://localhost:3000/api/sessions");
     const result = await wrapped(req);
 
@@ -155,7 +155,7 @@ describe("withTiming", () => {
   it("handles non-Error thrown values", async () => {
     const innerHandler = vi.fn().mockRejectedValue("string error");
 
-    const wrapped = withTiming(innerHandler, "test-route");
+    const wrapped = withTiming(innerHandler);
     const req = new Request("http://localhost:3000/api/sessions");
     const result = await wrapped(req);
 
@@ -171,7 +171,7 @@ describe("withTiming", () => {
       return new Response("ok", { status: 200 });
     });
 
-    const wrapped = withTiming(innerHandler, "test-route");
+    const wrapped = withTiming(innerHandler);
     const req = new Request("http://localhost:3000/api/sessions");
     await wrapped(req);
 
@@ -188,7 +188,7 @@ describe("extractSessionId (indirect via withTiming)", () => {
       new Response("ok", { status: 200 }),
     );
 
-    const wrapped = withTiming(innerHandler, "test-route");
+    const wrapped = withTiming(innerHandler);
     const req = new Request("http://localhost:3000/api/sessions/abc123");
     await wrapped(req);
 
@@ -201,7 +201,7 @@ describe("extractSessionId (indirect via withTiming)", () => {
       new Response("ok", { status: 200 }),
     );
 
-    const wrapped = withTiming(innerHandler, "test-route");
+    const wrapped = withTiming(innerHandler);
     const req = new Request("http://localhost:3000/api/sessions/ao-1/kill");
     await wrapped(req);
 
@@ -214,7 +214,7 @@ describe("extractSessionId (indirect via withTiming)", () => {
       new Response("ok", { status: 200 }),
     );
 
-    const wrapped = withTiming(innerHandler, "test-route");
+    const wrapped = withTiming(innerHandler);
     const req = new Request("http://localhost:3000/api/sessions");
     await wrapped(req);
 
@@ -227,7 +227,7 @@ describe("extractSessionId (indirect via withTiming)", () => {
       new Response("ok", { status: 200 }),
     );
 
-    const wrapped = withTiming(innerHandler, "test-route");
+    const wrapped = withTiming(innerHandler);
     const req = new Request("http://localhost:3000/api/prs/42/merge");
     await wrapped(req);
 
@@ -240,7 +240,7 @@ describe("extractSessionId (indirect via withTiming)", () => {
       new Response("ok", { status: 200 }),
     );
 
-    const wrapped = withTiming(innerHandler, "test-route");
+    const wrapped = withTiming(innerHandler);
     const req = new Request("http://localhost:3000/api/config");
     await wrapped(req);
 
@@ -253,7 +253,7 @@ describe("extractSessionId (indirect via withTiming)", () => {
       new Response("ok", { status: 200 }),
     );
 
-    const wrapped = withTiming(innerHandler, "test-route");
+    const wrapped = withTiming(innerHandler);
     const req = new Request(
       "http://localhost:3000/api/sessions/session%20with%20spaces",
     );

packages/web/src/lib/with-timing.ts

@@ -20,7 +20,7 @@ function extractSessionId(path: string): string | null {
  * Wrap a route handler with timing instrumentation.
  * Logs method, path, status code, and duration for every request.
  */
-export function withTiming(handler: RouteHandler, _routeName: string): RouteHandler {
+export function withTiming(handler: RouteHandler): RouteHandler {
   return async (req: Request, ctx?: unknown) => {
     const start = Date.now();
     const url = new URL(req.url);