feat: spaces redesign, model selector, auth fixes

Spaces:
- Perplexity-like UI with collaboration features
- Space detail page with threads/members tabs
- Invite members via email, role management
- New space creation with icon/color picker

Model selector:
- Added Ollama client for free Auto model
- GooSeek 1.0 via Timeweb (tariff-based)
- Frontend model dropdown in ChatInput

Auth & Infrastructure:
- Fixed auth-svc missing from Dockerfile.all
- Removed duplicate ratelimit_tiered.go (conflict)
- Added Redis to api-gateway for rate limiting
- Fixed Next.js proxy for local development

UI improvements:
- Redesigned login button in sidebar (gradient)
- Settings page with tabs (account/billing/prefs)
- Auth pages visual refresh

Made-with: Cursor

backend/pkg/middleware/ratelimit_redis.go

@@ -144,6 +144,7 @@ type TieredRateLimitConfig struct {
 	RedisClient *redis.Client
 	KeyPrefix   string
 	Tiers       map[string]TierConfig
+	DefaultTier string
 	GetTierFunc func(*fiber.Ctx) string
 	KeyFunc     func(*fiber.Ctx) string
 }
@@ -157,16 +158,31 @@ func TieredRateLimit(cfg TieredRateLimitConfig) fiber.Handler {
 	if cfg.KeyPrefix == "" {
 		cfg.KeyPrefix = "ratelimit:tiered"
 	}
+	if cfg.DefaultTier == "" {
+		cfg.DefaultTier = "free"
+	}
 	if cfg.GetTierFunc == nil {
-		cfg.GetTierFunc = func(c *fiber.Ctx) string { return "default" }
+		cfg.GetTierFunc = func(c *fiber.Ctx) string {
+			tier := GetUserTier(c)
+			if tier == "" {
+				return cfg.DefaultTier
+			}
+			return tier
+		}
 	}
 	if cfg.KeyFunc == nil {
-		cfg.KeyFunc = func(c *fiber.Ctx) string { return c.IP() }
+		cfg.KeyFunc = func(c *fiber.Ctx) string {
+			userID := GetUserID(c)
+			if userID != "" {
+				return "user:" + userID
+			}
+			return "ip:" + c.IP()
+		}
 	}
 
-	defaultTier := TierConfig{Max: 60, Window: time.Minute}
-	if _, ok := cfg.Tiers["default"]; !ok {
-		cfg.Tiers["default"] = defaultTier
+	defaultTierCfg := TierConfig{Max: 60, Window: time.Minute}
+	if _, ok := cfg.Tiers[cfg.DefaultTier]; !ok {
+		cfg.Tiers[cfg.DefaultTier] = defaultTierCfg
 	}
 
 	return func(c *fiber.Ctx) error {
@@ -174,7 +190,7 @@ func TieredRateLimit(cfg TieredRateLimitConfig) fiber.Handler {
 		tier := cfg.GetTierFunc(c)
 		tierCfg, ok := cfg.Tiers[tier]
 		if !ok {
-			tierCfg = cfg.Tiers["default"]
+			tierCfg = cfg.Tiers[cfg.DefaultTier]
 		}
 
 		key := fmt.Sprintf("%s:%s:%s", cfg.KeyPrefix, tier, cfg.KeyFunc(c))