fix(reports): stop the 'first N rows' option failing on large exports

The export path used one number for two different things: the format's hard
row cap, and the caller's explicit 'give me the first N rows'. Because
resolveExportCap() returned min(requested, formatCap) and runAll() then threw
when the result reached it, picking 'Records: First 100' in the export dialog
400'd on any report with more than 100 rows — the user asked to be truncated
and got an error instead.

Splits them: formatRowCap() is the hard, non-caller-controllable ceiling that
still throws when exceeded (a silently short file hides missing rows), while
resolveRowLimit() is the deliberate truncation and is honoured by slicing.
Verified against a 223-row dataset: limit=5 now returns 5 rows, and no limit
returns all 223.

apps/edr-freight-api/src/modules/reports/report-runner.service.ts

@@ -122,12 +122,19 @@ export class ReportRunnerService {
     };
   }
 
-  /** Same query, no paging — used by the export path. */
+  /**
+   * Same query, no paging — used by the export path.
+   *
+   * `limit` is the caller's deliberate "first N" (the dialog's "Records: First
+   * 100"), honoured by truncating. `cap` is the format's hard ceiling, which
+   * throws instead. These used to be one number, which made "First 100" fail
+   * outright on any report with more than 100 rows.
+   */
   async runAll(
     def: ReportDefinition,
     raw: RawReportQuery,
     directions: string[] | null,
-    limit: number,
+    { cap, limit }: { cap: number; limit?: number },
   ): Promise<{ columns: typeof def.columns; items: Record<string, unknown>[]; kpis: ReportRunResult['kpis'] }> {
     const params = coerceParams(def, raw);
     const ctx = { ds: this.ds, params, directions };
@@ -136,14 +143,19 @@ export class ReportRunnerService {
     // export is supposed to match what the user is looking at.
     const sort = resolveSort(def, raw.sortBy, raw.sortOrder);
     if (sort) qb.orderBy(sort.expr, sort.dir);
-    // limit + 1: fetching exactly `limit` cannot distinguish "there are exactly
-    // limit rows" from "there are more" — which is why the old `>= limit` check
-    // rejected a legitimate export of exactly the cap.
-    const items = await qb.limit(limit + 1).getRawMany();
-    if (items.length > limit) {
-      throw new BadRequestException(
-        `Export exceeds the ${limit}-row cap for this format. Narrow the filters.`,
-      );
+
+    const ceiling = limit ?? cap;
+    // ceiling + 1: fetching exactly `ceiling` cannot distinguish "there are
+    // exactly that many rows" from "there are more" — which is why the old
+    // `>= limit` check rejected a legitimate export of exactly the cap.
+    const items = await qb.limit(ceiling + 1).getRawMany();
+    if (items.length > ceiling) {
+      if (limit === undefined) {
+        throw new BadRequestException(
+          `Export exceeds the ${cap}-row cap for this format. Narrow the filters.`,
+        );
+      }
+      items.length = limit;
     }
     const kpis = def.summary ? await def.summary(ctx) : [];
     return { columns: def.columns, items, kpis };

apps/edr-freight-api/src/modules/reports/reports.controller.ts

@@ -12,9 +12,10 @@ import { FREIGHT_PERMS, reportPermissionKey } from '../../seed/freight-permissio
 import { UserTradeAccessService } from '../user-trade-access/user-trade-access.service';
 import {
   EXPORT_MIME,
+  formatRowCap,
   pickByKey,
-  resolveExportCap,
   resolveExportFormat,
+  resolveRowLimit,
 } from '../exports/export-request.util';
 import { TabularExportService } from '../exports/tabular-export.service';
 import { RawReportQuery, ReportRunnerService } from './report-runner.service';
@@ -101,10 +102,12 @@ export class ReportsController {
     const def = this.resolve(key, user);
     const directions = await this.userTradeAccessService.resolveAllowedDirections(user);
     const format = resolveExportFormat(query.format);
-    const cap = resolveExportCap(format, query.limit);
     const exportColumns = pickByKey(def.columns, query.fields);
 
-    const { items, kpis } = await this.runner.runAll(def, query, directions, cap);
+    const { items, kpis } = await this.runner.runAll(def, query, directions, {
+      cap: formatRowCap(format),
+      limit: resolveRowLimit(format, query.limit),
+    });
     const doc = {
       title: def.title,
       description: def.description,