feat: Dispo V2 import — API router + admin UI

API Router (packages/api/src/router/dispo.ts):
- 12 adminProcedure endpoints wired to existing application layer
- stageImportBatch, validateImportBatch, commitImportBatch
- listImportBatches, getImportBatch, cancelImportBatch
- listStagedResources/Projects/Assignments/Vacations/Unresolved
- resolveStagedRecord (APPROVE/REJECT/SKIP actions)

Admin UI:
- /admin/dispo-imports — batch list with status filter, new import modal
- /admin/dispo-imports/[batchId] — detail with 6 tabs:
  Summary, Resources, Projects, Assignments, Vacations, Unresolved
- Unresolved review queue with approve/skip per-record actions
- Commit workflow with pre-validation and progress indicator
- Sidebar nav link under Admin

Also fixes: timeline filter dropdown z-index (toolbar relative z-20)

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

packages/api/src/router/index.ts

@@ -9,6 +9,7 @@ import { clientRouter } from "./client.js";
 import { commentRouter } from "./comment.js";
 import { countryRouter } from "./country.js";
 import { dashboardRouter } from "./dashboard.js";
+import { dispoRouter } from "./dispo.js";
 import { effortRuleRouter } from "./effort-rule.js";
 import { experienceMultiplierRouter } from "./experience-multiplier.js";
 import { estimateRouter } from "./estimate.js";
@@ -36,6 +37,7 @@ import { webhookRouter } from "./webhook.js";
 export const appRouter = createTRPCRouter({
   assistant: assistantRouter,
   dashboard: dashboardRouter,
+  dispo: dispoRouter,
   effortRule: effortRuleRouter,
   experienceMultiplier: experienceMultiplierRouter,
   estimate: estimateRouter,