Timeline: place dots by co-op stage at the event date

Each date-field event is now plotted on the lane corresponding to the Framework Stage the co-op was in on the field's stored date, resolved from the activity stream's stage transitions. Date_Opened is pinned to Stage 5 as the journey anchor. Events that pre-date any known transition fall back to the field's section rank so they still surface somewhere. Extracts the STAGE_RANK map (previously inline in ReportView) into lib/stageRank.ts alongside the new buildStageRankAtDate resolver factory.

components/ReportView.tsx

@@ -10,6 +10,7 @@ import type {
   StageSectionConfig,
 } from "@/types/form";
 import { STAGE_OPTION_GROUP_ID } from "@/config/form";
+import { STAGE_RANK, buildStageRankAtDate } from "@/lib/stageRank";
 import { StageIcon } from "./StageIcon";
 import {
   FieldHistoryGroup,
@@ -39,15 +40,6 @@ type LoadState =
 
 type PathwayState = "past" | "current" | "future";
 
-const STAGE_RANK: Record<string, number> = {
-  Inquiry: 0,
-  Organizing: 1,
-  Feasibility: 2,
-  "Business feasibility": 3,
-  "Store Implementation": 4,
-  "Stabilize newly opened co-op": 5,
-};
-
 export function ReportView({ config, cid, cs }: ReportViewProps) {
   const [load, setLoad] = useState<LoadState>({ kind: "loading" });
 
@@ -126,7 +118,11 @@ export function ReportView({ config, cid, cs }: ReportViewProps) {
         dateRange={dateRange}
       />
 
-      <DateTimeline sections={config.sections} fieldHistory={data.fieldHistory} />
+      <DateTimeline
+        sections={config.sections}
+        fieldHistory={data.fieldHistory}
+        stageRankAtDate={buildStageRankAtDate(data.activities)}
+      />
 
       {sectionsToRender.length === 0 ? (
         <EmptyState />