feat(mobile): mobile-responsive UI — bottom tab bar, bottom-sheet dialogs, PWA

All changes are gated behind max-md:/md:hidden so the >=768px desktop layout is untouched (verified with lint + build + live checks at 375px).

- globals.css: one mobile block — 16px inputs (no iOS auto-zoom), units sidebar stacks above content, wizard item rows become 2-col (text fields full-width, delete button full-width), dd-panels / flow diagram / conv-form stack, larger touch targets
- ui/dialog.tsx: dialogs become full-width bottom sheets on mobile (all modals inherit it); desktop keeps the centered dialog
- Header: sticky on mobile only + PageLayout bottom clearance
- New MobileTabBar: role-aware bottom tabs (office admin/manager, inventory PM, inventory admin); hidden on /wizard
- Wizard step 4: TouchSensor (150ms delay) so touch drag works without stealing scroll
- JalaliDatePicker: dropdown capped to viewport; bigger day cells and time inputs on mobile
- PWA: manifest.webmanifest + 192/512 icons (scripts/gen-pwa-icons.ps1) + theme-color/manifest links in index.html
- New docs/mobile-responsive.md documenting the full change set

frontend/src/components/JalaliDatePicker.tsx

@@ -183,6 +183,8 @@ export function JalaliDatePicker({
         <div
           className={cn(
             "absolute inset-x-0 top-full z-30 mt-1 rounded-md border border-line bg-panel shadow-md",
+            // حداکثر عرض = viewport (موبایل باریک سرریز نمی‌شود؛ دسکتاپ بی‌تغییر)
+            "max-w-[calc(100vw-2rem)]",
             withTime ? "w-80 p-3" : "w-64 p-2",
           )}
         >
@@ -217,7 +219,7 @@ export function JalaliDatePicker({
                   key={i}
                   type="button"
                   className={cn(
-                    "cursor-pointer rounded py-0.5 text-[12px] hover:bg-slate-bg",
+                    "cursor-pointer rounded py-0.5 text-[12px] hover:bg-slate-bg max-md:py-1.5",
                     cell.isToday && !selectedIso && "bg-blue-bg font-bold text-[#1d4ed8]",
                     cell.isToday && selectedIso && "font-bold text-[#1d4ed8]",
                     cell.iso === selectedIso && "bg-accent text-white hover:bg-accent-dark",
@@ -235,7 +237,7 @@ export function JalaliDatePicker({
                 <span className="text-[11.5px] font-semibold text-muted">ساعت</span>
                 <input
                   type="text"
-                  className="num-input h-8 w-14 rounded-md border border-line bg-panel px-1 text-center text-[13px] tabular-nums focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-accent/40"
+                  className="num-input h-8 w-14 rounded-md border border-line bg-panel px-1 text-center text-[13px] tabular-nums focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-accent/40 max-md:h-10 max-md:w-16"
                   value={faNum(String(time.h).padStart(2, "0"))}
                   inputMode="numeric"
                   maxLength={2}
@@ -247,7 +249,7 @@ export function JalaliDatePicker({
                 <span className="text-[11.5px] font-semibold text-muted">دقیقه</span>
                 <input
                   type="text"
-                  className="num-input h-8 w-14 rounded-md border border-line bg-panel px-1 text-center text-[13px] tabular-nums focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-accent/40"
+                  className="num-input h-8 w-14 rounded-md border border-line bg-panel px-1 text-center text-[13px] tabular-nums focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-accent/40 max-md:h-10 max-md:w-16"
                   value={faNum(String(time.m).padStart(2, "0"))}
                   inputMode="numeric"
                   maxLength={2}