perf(server): the Pull Requests page no longer burns GitHub's GraphQL budget while agents run#20093

@@ -1249,48 +1255,73 @@ export const make = Effect.gen(function* () {
         }).pipe(
           observeRead,
           Effect.flatMap(({ value: page, observedAt }) =>
-            Effect.flatMap(Clock.currentTimeMillis, (now) => {
+            Effect.gen(function* () {
+              const now = yield* Clock.currentTimeMillis;
               const rows = new Map<string, Array<ProviderChangeRequest>>();
-              for (const [key, visibleAt] of searchVisibleAt) {
-                if (now - visibleAt > Duration.toMillis(SEARCH_VISIBILITY_TTL)) {
-                  searchVisibleAt.delete(key);
+              for (const [key, held] of searchCoverageCache) {
+                if (now - held.at > Duration.toMillis(SEARCH_VISIBILITY_TTL)) {
+                  searchCoverageCache.delete(key);
                 }
               }
               for (const item of page.items) {
                 const key = item.repository.trim().toLowerCase();
                 const held = rows.get(key);
                 if (held === undefined) rows.set(key, [item]);
                 else held.push(item);
-                searchVisibleAt.set(searchVisibilityKey(first.host, item.repository), now);
+                searchCoverageCache.set(searchCoverageKey(first.host, item.repository), {
+                  at: now,
+                  covered: true,
+                });
               }
               const boundary = page.items.reduce<string | null>(
                 (oldest, item) =>
                   oldest === null || item.updatedAt < oldest ? item.updatedAt : oldest,
                 null,
               );
-              return Effect.forEach(
+              // Silence on the first page can mean an unindexed repository. Later pages already
+              // have a search boundary, so their missing rows are older than that boundary.
+              const silent = chunk.filter(
+                (project) =>
+                  !rows.has(project.repository.trim().toLowerCase()) &&
+                  cursorOf(project) === undefined,
+              );
+              const unasked = silent.filter(
+                (project) =>
+                  !searchCoverageCache.has(searchCoverageKey(project.host, project.repository)),
+              );
+              const searchCoverage = first.api.searchCoverage;
+              if (unasked.length > 0 && searchCoverage !== undefined) {
+                const answers = yield* searchCoverage({
+                  cwd: first.project.workspaceRoot,
+                  host: first.host,
+                  repositories: unasked.map((project) => project.repository),
+                }).pipe(Effect.orElseSucceed(() => []));
+                // Missing answers and failed probes retain the per-repository fallback.
+                for (const project of unasked) {
+                  searchCoverageCache.set(searchCoverageKey(project.host, project.repository), {
+                    at: now,
+                    covered: false,
+                  });
+                }