feat: Update project and contract terminology for consistency in UI and translations

src/app/contracts/page.js

@@ -177,7 +177,19 @@ export default function ContractsMainPage() {
 				>
 					<Link href="/contracts/new">
 						<Button variant="primary" size="lg">
-							<span className="mr-2">➕</span>
+							<svg
+								className="w-5 h-5 mr-2"
+								fill="none"
+								stroke="currentColor"
+								viewBox="0 0 24 24"
+							>
+								<path
+									strokeLinecap="round"
+									strokeLinejoin="round"
+									strokeWidth={2}
+									d="M12 4v16m8-8H4"
+								/>
+							</svg>
 							{t('contracts.newContract')}
 						</Button>
 					</Link>
@@ -232,7 +244,19 @@ export default function ContractsMainPage() {
 			>
 				<Link href="/contracts/new">
 					<Button variant="primary" size="lg">
-						<span className="mr-2">➕</span>
+						<svg
+								className="w-5 h-5 mr-2"
+								fill="none"
+								stroke="currentColor"
+								viewBox="0 0 24 24"
+							>
+								<path
+									strokeLinecap="round"
+									strokeLinejoin="round"
+									strokeWidth={2}
+									d="M12 4v16m8-8H4"
+								/>
+							</svg>
 						{t('contracts.newContract')}
 					</Button>
 				</Link>{" "}