fix: remove private data and update documentation

- Replace Pflugerville with SITER in SVG files
- Remove outdated -k option reference from README

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images/image-2.svg

@@ -12,7 +12,7 @@
   
   <!-- Title -->
   <text x="400" y="30" text-anchor="middle" font-family="Arial, sans-serif" font-size="18" font-weight="bold" fill="#1e293b">Monthly Solar Production Estimate (NREL PVWatts)</text>
-  <text x="400" y="50" text-anchor="middle" font-family="Arial, sans-serif" font-size="12" fill="#64748b">16 × 250W panels = 4.0 kW DC | SITER, Pflugerville, TX</text>
+  <text x="400" y="50" text-anchor="middle" font-family="Arial, sans-serif" font-size="12" fill="#64748b">16 × 250W panels = 4.0 kW DC | SITER, SITER, TX</text>
   
   <!-- Y-axis -->
   <line x1="80" y1="70" x2="80" y2="320" stroke="#cbd5e1" stroke-width="1"/>

images/v2-image-2.svg

@@ -16,7 +16,7 @@
 
   <!-- Title -->
   <text x="400" y="30" text-anchor="middle" font-family="Arial, sans-serif" font-size="18" font-weight="bold" fill="#1e293b">Solar Production vs Monthly Consumption</text>
-  <text x="400" y="50" text-anchor="middle" font-family="Arial, sans-serif" font-size="12" fill="#64748b">16 × 250W panels = 4.0 kW DC | SITER, Pflugerville, TX</text>
+  <text x="400" y="50" text-anchor="middle" font-family="Arial, sans-serif" font-size="12" fill="#64748b">16 × 250W panels = 4.0 kW DC | SITER, SITER, TX</text>
 
   <!-- Y-axis -->
   <line x1="80" y1="70" x2="80" y2="340" stroke="#cbd5e1" stroke-width="1"/>