UX Text Improvements: Add Keywords Page

- Updated page title: 'Add Keywords' → 'Find & Add Keywords to Your Site'
- Updated sector selection banner:
  * Header: 'Select a Sector to Add Keywords' → 'Choose a Topic Area First'
  * Description simplified and made more conversational
- Updated import modal:
  * Title: 'Import Seed Keywords' → 'Import Your Keywords'
  * CSV label: 'Upload CSV File' → 'Upload Your CSV File'
  * Column descriptions made more user-friendly

Part of comprehensive UX text improvement initiative.

frontend/src/pages/Setup/IndustriesSectorsKeywords.tsx

@@ -647,7 +647,7 @@ export default function IndustriesSectorsKeywords() {
     <>
       <PageMeta title="Add Keywords" description="Browse and add keywords to your workflow" />
       <PageHeader 
-        title="Add Keywords" 
+        title="Find & Add Keywords to Your Site" 
         badge={{ icon: <BoltIcon />, color: 'blue' }}
       />
       {/* Show info banner when no sector is selected */}
@@ -662,10 +662,10 @@ export default function IndustriesSectorsKeywords() {
               </div>
               <div className="flex-1">
                 <h3 className="text-sm font-medium text-blue-900 dark:text-blue-200">
-                  Select a Sector to Add Keywords
+                  Choose a Topic Area First
                 </h3>
                 <p className="mt-1 text-sm text-blue-700 dark:text-blue-300">
-                  Please select a sector from the dropdown above to enable adding keywords to your workflow. Keywords must be added to a specific sector.
+                  Select a topic area from the dropdown above to see relevant keywords. Keywords will be organized by topic area.
                 </p>
               </div>
             </div>
@@ -734,12 +734,12 @@ export default function IndustriesSectorsKeywords() {
       >
         <div className="p-6 space-y-4">
           <h2 className="text-xl font-semibold text-gray-900 dark:text-white mb-4">
-            Import Seed Keywords
+            Import Your Keywords
           </h2>
           <div>
-            <Label htmlFor="import-file">Upload CSV File</Label>
+            <Label htmlFor="import-file">Upload Your CSV File</Label>
             <p className="text-sm text-gray-500 dark:text-gray-400 mb-2">
-              Expected columns: keyword, volume, difficulty, country, industry_name, sector_name
+              Your CSV should have: keyword, monthly searches, competition level, location, industry, topic area
             </p>
             <FileInput
               accept=".csv"