feat: add Citations and WatchlistChat components, integrate with API

- Implemented Citations component to display citation data.
- Created WatchlistDrawer and ChatSidebar components for managing watchlists and AI chat functionality.
- Integrated API calls for watchlist management and chat interactions.
- Updated index.tsx to include new components in the main application layout.
- Added API client in lib/api.ts for structured API interactions.
- Developed Alerts, Dashboard, Portfolio, Routines, Screener, and Report pages with relevant data fetching and UI components.
- Introduced styles in tokens.css for consistent theming across the application.
- Configured TypeScript and Vite for project setup and development.

backend/internal/store/cache.go

@@ -0,0 +1,84 @@
+package store
+
+import (
+	"context"
+	"encoding/json"
+	"sync"
+	"time"
+
+	"github.com/redis/go-redis/v9"
+)
+
+// Cache wraps Redis with an in-memory TTL fallback so the demo runs without
+// REDIS_URL. Reference data (registry/taxonomy/tags) uses 24h TTL.
+type Cache struct {
+	rdb *redis.Client
+	mu  sync.Mutex
+	mem map[string]memEntry
+}
+
+type memEntry struct {
+	val string
+	exp time.Time
+}
+
+// NewCache builds a cache; empty redisURL selects the in-memory fallback.
+func NewCache(redisURL string) *Cache {
+	c := &Cache{mem: map[string]memEntry{}}
+	if redisURL != "" {
+		opt, err := redis.ParseURL(redisURL)
+		if err == nil {
+			c.rdb = redis.NewClient(opt)
+		}
+	}
+	return c
+}
+
+// HasRedis reports whether a live Redis backs this cache.
+func (c *Cache) HasRedis() bool { return c.rdb != nil }
+
+// Get returns the cached value or "" on miss/expiry.
+func (c *Cache) Get(ctx context.Context, key string) string {
+	if c.rdb != nil {
+		if v, err := c.rdb.Get(ctx, key).Result(); err == nil {
+			return v
+		}
+		return ""
+	}
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	e, ok := c.mem[key]
+	if !ok || time.Now().After(e.exp) {
+		return ""
+	}
+	return e.val
+}
+
+// Set stores a value with TTL.
+func (c *Cache) Set(ctx context.Context, key, val string, ttl time.Duration) {
+	if c.rdb != nil {
+		_ = c.rdb.Set(ctx, key, val, ttl).Err()
+		return
+	}
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	c.mem[key] = memEntry{val: val, exp: time.Now().Add(ttl)}
+}
+
+// GetJSON unmarshals a cached JSON value; ok=false on miss.
+func (c *Cache) GetJSON(ctx context.Context, key string, v any) bool {
+	raw := c.Get(ctx, key)
+	if raw == "" {
+		return false
+	}
+	return json.Unmarshal([]byte(raw), v) == nil
+}
+
+// SetJSON marshals and stores a value with TTL.
+func (c *Cache) SetJSON(ctx context.Context, key string, v any, ttl time.Duration) {
+	b, err := json.Marshal(v)
+	if err != nil {
+		return
+	}
+	c.Set(ctx, key, string(b), ttl)
+}