refactor: rename tab to KI-Signale, diversify DEMAND signal narratives

- "Digitale Signale" → "KI-Signale" tab label
- signal-001: Alpbach Advisors — new Zürich branch announced via press release
- signal-007: EBH Treuhand — Handelsregister merger of two Winterthur firms
- signal-010: Centra Schweiz — suburban→city relocation for talent attraction
- signal-013: Rheintaler Logistik Solutions — spin-off needs its own premises
- signal-015: BernTech — CEO publicly confirmed new office in VC press release
- signal-004 improved: lab expansion driven by published strategic plan, not headcount
- Each signal uses a different trigger: press/Handelsregister/annual report/VC round

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

src/pages/supply/MarketIntelligence.tsx

@@ -1064,11 +1064,11 @@ export default function MarketIntelligence() {
           '& .MuiTab-root': { textTransform: 'none', fontSize: '0.85rem', minHeight: 44, px: 3 },
         }}
       >
-        <Tab icon={<Sparkles size={14} />} iconPosition="start" label="Digitale Signale" />
+        <Tab icon={<Sparkles size={14} />} iconPosition="start" label="KI-Signale" />
         <Tab icon={<Users size={14} />} iconPosition="start" label="Netzwerk" />
       </Tabs>
 
-      {/* Tab 0: Digitale Signale */}
+      {/* Tab 0: KI-Signale */}
       {activeTab === 0 && (
         <Box sx={{ display: 'flex', flex: 1, overflow: 'hidden' }}>
           {/* Left pane */}