feat: responsive layout + Reminder Manager redesign

- Auto-collapse sidebar at <1536px (all laptops), expand at ≥1536px
- Responsive drawer/panel widths across Pipeline, Properties, MyListings, Anfragen, MatchDetail, AISearch
- Reminder Manager: dot+label priority badge, Fläche column removed, status only for non-active rows
- ReminderKpiBar: focal Überfällig card, three secondary KPIs
- ReminderDetailDrawer: Task Panel redesign — Finanzen removed, Notiz promoted, Pre-Market as inline badge, full create form
- useCreateReminder hook wired to reminderService.create with cache invalidation
- Mock data: contract-derived reminders (LEASE_EXPIRY, BREAK_OPTION, RENT_REVIEW, INSURANCE_RENEWAL, SCHATTENMARKT_RELEASE) now show auto-creation note in Verlauf

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/pages/demand/AISearch.tsx

@@ -221,7 +221,7 @@ export default function AISearch() {
 
         {/* IDLE: full form */}
         {(step === NeedBuilderStep.IDLE || step === NeedBuilderStep.PARSING) && (
-          <Box sx={{ display: 'flex', flexDirection: 'column', gap: 3, maxWidth: 1200, mx: 'auto' }}>
+          <Box sx={{ display: 'flex', flexDirection: 'column', gap: 3, maxWidth: { md: 900, xl: 1200 }, mx: 'auto' }}>
             <VoiceNeedInput
               text={inputText}
               onTextChange={handleTextChange}

src/pages/demand/Anfragen.tsx

@@ -134,8 +134,8 @@ export default function Anfragen() {
       {/* ── Left panel ── */}
       <Box
         sx={{
-          width: { xs: mobileShowChat ? 0 : '100%', md: 320 },
-          minWidth: { md: 320 },
+          width: { xs: mobileShowChat ? 0 : '100%', md: 280, lg: 300, xl: 320 },
+          minWidth: { md: 280, lg: 300, xl: 320 },
           flexShrink: 0,
           display: 'flex', flexDirection: 'column',
           borderRight: `1px solid ${DS_BORDER.default}`,

src/pages/demand/MatchDetail.tsx

@@ -171,7 +171,7 @@ export default function MatchDetail() {
       />
 
       {/* ── Main content ── */}
-      <Box sx={{ maxWidth: { sm: 780, md: 960, lg: 1100 }, mx: 'auto', px: { xs: 1.5, sm: 3 }, py: { xs: 2, sm: 3 }, display: 'flex', flexDirection: 'column', gap: 2 }}>
+      <Box sx={{ maxWidth: { sm: 700, md: 860, lg: 1000, xl: 1100 }, mx: 'auto', px: { xs: 1.5, sm: 3 }, py: { xs: 2, sm: 3 }, display: 'flex', flexDirection: 'column', gap: 2 }}>
 
         {/* ── Section A: Warum dieser Match? ── */}
         <Paper sx={{ p: 2.5 }}>

src/pages/demand/Pipeline.tsx

@@ -109,7 +109,7 @@ export default function Pipeline() {
               return (
                 <Box
                   key={stage.key}
-                  sx={{ minWidth: syncedSelected ? 190 : 230, maxWidth: syncedSelected ? 230 : 270, flexShrink: 0, display: 'flex', flexDirection: 'column' }}
+                  sx={{ minWidth: syncedSelected ? 170 : 200, maxWidth: syncedSelected ? 210 : 260, flexShrink: 0, display: 'flex', flexDirection: 'column' }}
                 >
                   <Box sx={{ py: 1, display: 'flex', alignItems: 'center', gap: 1 }}>
                     <Typography sx={{ fontWeight: 700, color: stage.color, fontSize: '0.8125rem' }}>

src/pages/supply/MyListings.tsx

@@ -425,7 +425,7 @@ export default function MyListings() {
         anchor="right"
         open={!!detailId}
         onClose={() => setDetailId(null)}
-        slotProps={{ paper: { sx: { width: { xs: '100%', sm: 560 } } } }}
+        slotProps={{ paper: { sx: { width: { xs: '100%', sm: '90vw', md: 480, lg: 540, xl: 560 } } } }}
       >
         {detailId && (
           <PropertyDetailView propertyId={detailId} onClose={() => setDetailId(null)} hideTabs={['Matchability', 'Marktsignale']} />

src/pages/supply/Properties.tsx

@@ -247,7 +247,7 @@ export default function Properties() {
         anchor="right"
         open={!!selectedId}
         onClose={() => setSelectedId(null)}
-        slotProps={{ paper: { sx: { width: isMobile ? '100vw' : 650, boxShadow: '-4px 0 24px rgba(0,0,0,0.10)' } } }}
+        slotProps={{ paper: { sx: { width: isMobile ? '100vw' : { md: 520, lg: 580, xl: 640 }, boxShadow: '-4px 0 24px rgba(0,0,0,0.10)' } } }}
       >
         {selectedId && (
           <PropertyDetailView propertyId={selectedId} onClose={() => setSelectedId(null)} />