Remove unused components and assets from the project

Deleted unused components (Attachments, CustomMarkdownRenderer, EnableSearchButton, FlyoutSubMenu) and associated styles (katex.css) to streamline the codebase. This cleanup helps reduce technical debt and improve project maintainability.

src/components/WelcomeHome.tsx

@@ -0,0 +1,83 @@
+import { motion } from "framer-motion";
+import { Box, Center, VStack } from "@chakra-ui/react";
+import {
+  welcome_home_text,
+  welcome_home_tip,
+} from "../static-data/welcome_home_text";
+import {renderMarkdown} from "./markdown/MarkdownComponent";
+
+
+function WelcomeHomeMessage({ visible }) {
+  const containerVariants = {
+    visible: {
+      transition: {
+        staggerChildren: 0.15,
+      },
+    },
+    hidden: {
+      transition: {
+        staggerChildren: 0.05,
+        staggerDirection: -1,
+      },
+    },
+  };
+
+  const textVariants = {
+    visible: {
+      opacity: 1,
+      y: 0,
+      transition: {
+        duration: 0.5,
+        ease: [0.165, 0.84, 0.44, 1],
+      },
+    },
+    hidden: {
+      opacity: 0,
+      y: 20,
+      transition: {
+        duration: 0.3,
+        ease: [0.165, 0.84, 0.44, 1],
+      },
+    },
+  };
+
+  return (
+    <Center>
+      <VStack spacing={8} align="center" maxW="400px">
+        {/* Welcome Message */}
+        <Box
+          fontSize="sm"
+          fontStyle="italic"
+          textAlign="center"
+          color="text.secondary"
+          mt={4}
+        >
+          <motion.div
+            variants={containerVariants}
+            initial="hidden"
+            animate={visible ? "visible" : "hidden"}
+          >
+            <Box userSelect={"none"}>
+              <motion.div variants={textVariants}>
+                {renderMarkdown(welcome_home_text)}
+              </motion.div>
+            </Box>
+          </motion.div>
+        </Box>
+        <motion.div variants={textVariants}>
+          <Box
+            fontSize="sm"
+            fontStyle="italic"
+            textAlign="center"
+            color="text.secondary"
+            mt={1}
+          >
+            {renderMarkdown(welcome_home_tip)}
+          </Box>
+        </motion.div>
+      </VStack>
+    </Center>
+  );
+}
+
+export default WelcomeHomeMessage;