Initial commit: TKB Timeshift Schedule Management Application

- Next.js 15.2.4 with React 19 and TypeScript
- Monthly schedule generator with Excel-like formatting
- Complete employee list from example.xlsx (18 employees)
- Excel-style column naming (A, B, C, ..., Z, AA, AB, ...)
- Counter-clockwise text rotation for data values
- Weekend highlighting and shift color coding
- Team selection for TKB, METRO, D8
- 7 days from previous month + full current month date range
- jspreadsheet integration for Excel-like interface

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

app/page.tsx

@@ -0,0 +1,52 @@
+"use client"
+
+import * as React from "react"
+import { TeamSidebar } from "@/components/team-sidebar"
+import { ScheduleTabs } from "@/components/schedule-tabs"
+import {
+  Breadcrumb,
+  BreadcrumbItem,
+  BreadcrumbLink,
+  BreadcrumbList,
+  BreadcrumbPage,
+  BreadcrumbSeparator,
+} from "@/components/ui/breadcrumb"
+import { Separator } from "@/components/ui/separator"
+import { SidebarInset, SidebarProvider, SidebarTrigger } from "@/components/ui/sidebar"
+
+// Team data for display
+const teamData = {
+  tkb: "TKB",
+  metro: "METRO",
+  d8: "D8",
+}
+
+export default function TimeshiftManager() {
+  const [selectedTeam, setSelectedTeam] = React.useState("tkb")
+
+  return (
+    <SidebarProvider>
+      <TeamSidebar selectedTeam={selectedTeam} onTeamSelect={setSelectedTeam} />
+      <SidebarInset>
+        <header className="flex h-16 shrink-0 items-center gap-2 border-b px-4">
+          <SidebarTrigger className="-ml-1" />
+          <Separator orientation="vertical" className="mr-2 h-4" />
+          <Breadcrumb>
+            <BreadcrumbList>
+              <BreadcrumbItem className="hidden md:block">
+                <BreadcrumbLink href="#">TimeShift 161</BreadcrumbLink>
+              </BreadcrumbItem>
+              <BreadcrumbSeparator className="hidden md:block" />
+              <BreadcrumbItem>
+                <BreadcrumbPage>{teamData[selectedTeam as keyof typeof teamData]}</BreadcrumbPage>
+              </BreadcrumbItem>
+            </BreadcrumbList>
+          </Breadcrumb>
+        </header>
+        <div className="flex flex-1 flex-col gap-4 p-4">
+          <ScheduleTabs teamId={selectedTeam} teamName={teamData[selectedTeam as keyof typeof teamData]} />
+        </div>
+      </SidebarInset>
+    </SidebarProvider>
+  )
+}