Migrate from Gin to Echo framework and add comprehensive integration tests

Major changes:
- Migrate all handlers from Gin to Echo framework
- Add new apperrors, echohelpers, and validator packages
- Update middleware for Echo compatibility
- Add ArchivedHandler to task categorization chain (archived tasks go to cancelled_tasks column)
- Add 6 new integration tests:
  - RecurringTaskLifecycle: NextDueDate advancement for weekly/monthly tasks
  - MultiUserSharing: Complex sharing with user removal
  - TaskStateTransitions: All state transitions and kanban column changes
  - DateBoundaryEdgeCases: Threshold boundary testing
  - CascadeOperations: Residence deletion cascade effects
  - MultiUserOperations: Shared residence collaboration
- Add single-purpose repository functions for kanban columns (GetOverdueTasks, GetDueSoonTasks, etc.)
- Fix RemoveUser route param mismatch (userId -> user_id)
- Fix determineExpectedColumn helper to correctly prioritize in_progress over overdue

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

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

pkg/utils/logger.go

@@ -5,7 +5,7 @@ import (
 	"os"
 	"time"
 
-	"github.com/gin-gonic/gin"
+	"github.com/labstack/echo/v4"
 	"github.com/rs/zerolog"
 	"github.com/rs/zerolog/log"
 )
@@ -57,66 +57,75 @@ func InitLoggerWithWriter(debug bool, additionalWriter io.Writer) {
 	log.Logger = zerolog.New(output).With().Timestamp().Caller().Logger()
 }
 
-// GinLogger returns a Gin middleware for request logging
-func GinLogger() gin.HandlerFunc {
-	return func(c *gin.Context) {
-		start := time.Now()
-		path := c.Request.URL.Path
-		raw := c.Request.URL.RawQuery
+// EchoLogger returns an Echo middleware for request logging
+func EchoLogger() echo.MiddlewareFunc {
+	return func(next echo.HandlerFunc) echo.HandlerFunc {
+		return func(c echo.Context) error {
+			start := time.Now()
+			req := c.Request()
+			path := req.URL.Path
+			raw := req.URL.RawQuery
 
-		// Process request
-		c.Next()
+			// Process request
+			err := next(c)
 
-		// Log after request
-		end := time.Now()
-		latency := end.Sub(start)
+			// Log after request
+			end := time.Now()
+			latency := end.Sub(start)
 
-		if raw != "" {
-			path = path + "?" + raw
-		}
-
-		msg := "Request"
-		if len(c.Errors) > 0 {
-			msg = c.Errors.String()
-		}
-
-		event := log.Info()
-		statusCode := c.Writer.Status()
-
-		if statusCode >= 400 && statusCode < 500 {
-			event = log.Warn()
-		} else if statusCode >= 500 {
-			event = log.Error()
-		}
-
-		event.
-			Str("method", c.Request.Method).
-			Str("path", path).
-			Int("status", statusCode).
-			Str("ip", c.ClientIP()).
-			Dur("latency", latency).
-			Str("user-agent", c.Request.UserAgent()).
-			Msg(msg)
-	}
-}
-
-// GinRecovery returns a Gin middleware for panic recovery
-func GinRecovery() gin.HandlerFunc {
-	return func(c *gin.Context) {
-		defer func() {
-			if err := recover(); err != nil {
-				log.Error().
-					Interface("error", err).
-					Str("path", c.Request.URL.Path).
-					Str("method", c.Request.Method).
-					Msg("Panic recovered")
-
-				c.AbortWithStatusJSON(500, gin.H{
-					"error": "Internal server error",
-				})
+			if raw != "" {
+				path = path + "?" + raw
 			}
-		}()
 
-		c.Next()
+			res := c.Response()
+			statusCode := res.Status
+
+			msg := "Request"
+			if err != nil {
+				msg = err.Error()
+			}
+
+			event := log.Info()
+
+			if statusCode >= 400 && statusCode < 500 {
+				event = log.Warn()
+			} else if statusCode >= 500 {
+				event = log.Error()
+			}
+
+			event.
+				Str("method", req.Method).
+				Str("path", path).
+				Int("status", statusCode).
+				Str("ip", c.RealIP()).
+				Dur("latency", latency).
+				Str("user-agent", req.UserAgent()).
+				Msg(msg)
+
+			return err
+		}
+	}
+}
+
+// EchoRecovery returns an Echo middleware for panic recovery
+func EchoRecovery() echo.MiddlewareFunc {
+	return func(next echo.HandlerFunc) echo.HandlerFunc {
+		return func(c echo.Context) error {
+			defer func() {
+				if err := recover(); err != nil {
+					log.Error().
+						Interface("error", err).
+						Str("path", c.Request().URL.Path).
+						Str("method", c.Request().Method).
+						Msg("Panic recovered")
+
+					c.JSON(500, map[string]interface{}{
+						"error": "Internal server error",
+					})
+				}
+			}()
+
+			return next(c)
+		}
 	}
 }