feat: harden support, localize knowledge and add operator availability [skip ci]

Source-only publication of reviewed commit 64e96a7f423673dc29ad56485be9fc79bce8af1c.

Passed in isolation: focused frontend/backend tests, race checks, TypeScript typecheck, lint, Go compilation, Flowgram build, and deterministic SDK build/tests.

Not accepted as a production release: Next.js export/native assembly remains blocked by environment memory limits; browser interaction and MySQL staging acceptance remain unverified. No production server, database/schema, runtime configuration, deployment, release tag, or workflow execution was performed.

Expected source tree: 0a4a7528e9.

web/app/(dashboard)/dashboard/agent-team-schedules/page.tsx

@@ -1,5 +1,7 @@
+// Modified in this independent fork for explicit dated/recurring calendar modes; see docs/hardening/README.md.
 "use client"
 
+import Link from "next/link"
 import { useCallback, useEffect, useMemo, useState } from "react"
 import {
   CalendarDaysIcon,
@@ -286,6 +288,7 @@ export default function DashboardAgentTeamSchedulesPage() {
   return (
     <>
       <div className="flex h-[calc(100vh-var(--header-height))] min-h-0 flex-1 flex-col gap-4 overflow-hidden p-4 lg:p-6">
+        <p className="shrink-0 rounded-md border bg-muted/30 p-3 text-xs text-muted-foreground">{t("supportAvailability.datedShiftsNotice")} <Link href="/dashboard/support-availability" className="underline underline-offset-2">{t("supportAvailability.title")}</Link></p>
         <div className="shrink-0 flex flex-col gap-3 xl:flex-row xl:items-center xl:justify-between">
           <div className="flex flex-wrap items-center gap-2">
             <ButtonGroup>