feat: complete audit coverage — comment, webhook, system-role, dispo, scenario

- comment.ts: create (body preview), resolve, delete
- webhook.ts: create, update, delete, test (result in summary)
- system-role-config.ts: update with before/after
- dispo.ts: commitImportBatch (IMPORT with counts), cancelImportBatch
- scenario.ts: applyScenario (CREATE with allocation count)

Audit coverage now: 29/36 routers (81%). Remaining 7 are read-only
(dashboard, staffing, chargeability-report, computation-graph,
report, insights.detectAnomalies, notification read/dismiss).

Co-Authored-By: claude-flow <ruv@ruv.net>

packages/api/src/router/scenario.ts

@@ -2,6 +2,7 @@ import { calculateAllocation, countWorkingDays } from "@planarchy/engine/allocat
 import { z } from "zod";
 import { TRPCError } from "@trpc/server";
 import { createTRPCRouter, controllerProcedure, protectedProcedure } from "../trpc.js";
+import { createAuditEntry } from "../lib/audit.js";
 
 const DEFAULT_AVAILABILITY = {
   monday: 8,
@@ -485,7 +486,7 @@ export const scenarioRouter = createTRPCRouter({
 
       const project = await ctx.db.project.findUnique({
         where: { id: projectId },
-        select: { id: true },
+        select: { id: true, name: true },
       });
       if (!project) {
         throw new TRPCError({ code: "NOT_FOUND", message: "Project not found" });
@@ -548,6 +549,18 @@ export const scenarioRouter = createTRPCRouter({
         created.push(newAssignment.id);
       }
 
+      void createAuditEntry({
+        db: ctx.db,
+        entityType: "ScenarioApplication",
+        entityId: projectId,
+        entityName: project.name,
+        action: "CREATE",
+        userId: ctx.dbUser?.id,
+        summary: `Applied scenario to project "${project.name}" (${created.length} allocations created/modified)`,
+        metadata: { appliedCount: created.length, assignmentIds: created },
+        source: "ui",
+      });
+
       return { appliedCount: created.length };
     }),
 });