fix: Improve text readability on light backgrounds

Fixed white/light text on white/light backgrounds across multiple pages by adding text-gray-900 classes to ensure proper contrast and readability. This addresses the issue where text was unreadable until hover/click on delegation, proposal, swap, and other pages.

Changes:
- DelegationManager: Added dark text to green-50 TabsList
- DelegateProfile: Fixed text color in blue-50 and green-50 Alert components
- ProposalWizard: Added dark text to green-50 success Alert
- Dashboard: Fixed text color in yellow-50 verification warning
- TokenSwap: Added dark text to all gray-50 and blue-50 containers (6 instances)
- DiscussionThread: Fixed markdown help card with gray-50 background
- FundingProposal: Added dark text to yellow-50 milestone warning

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

src/pages/Dashboard.tsx

@@ -198,12 +198,12 @@ export default function Dashboard() {
               </div>
               
               {!profile?.email_verified && (
-                <div className="border-l-4 border-yellow-500 bg-yellow-50 p-4">
+                <div className="border-l-4 border-yellow-500 bg-yellow-50 p-4 text-gray-900">
                   <div className="flex items-center">
                     <AlertCircle className="h-5 w-5 text-yellow-600 mr-2" />
                     <div>
-                      <h4 className="font-medium">Verify your email</h4>
-                      <p className="text-sm">Please verify your email to access all features</p>
+                      <h4 className="font-medium text-gray-900">Verify your email</h4>
+                      <p className="text-sm text-gray-900">Please verify your email to access all features</p>
                     </div>
                   </div>
                 </div>