refactor(server): update main entry point and docs for Echo v5

Update cmd/server/main.go and internal/docs/http_handler.go for Echo v5.

Changes in main.go:
- Update import from echo/v4 to echo/v5
- Replace echomiddleware.Logger() with RequestLogger()
- Remove net/http import (no longer needed)
- Update server startup to use app.StartServer()
  - Replaces direct echo.Start() call
  - Better separation of concerns

Changes in http_handler.go:
- Update handler signatures to use *echo.Context
- Ensure Echo v5 compatibility

These changes complete the server layer migration to Echo v5.

internal/docs/http_handler.go

@@ -8,8 +8,9 @@ import (
 
 	"bookhoard/internal/database"
 	"bookhoard/templates"
+
 	"github.com/google/uuid"
-	"github.com/labstack/echo/v4"
+	"github.com/labstack/echo/v5"
 )
 
 // HTTPHandler wraps the docs handler for Echo framework
@@ -25,7 +26,7 @@ func NewHTTPHandler(docsPath string) *HTTPHandler {
 }
 
 // ShowDocumentation renders a documentation page
-func (h *HTTPHandler) ShowDocumentation(c echo.Context) error {
+func (h *HTTPHandler) ShowDocumentation(c *echo.Context) error {
 	// Get the document path from URL parameter
 	docPath := c.Param("*")
 
@@ -101,7 +102,7 @@ func (h *HTTPHandler) ShowDocumentation(c echo.Context) error {
 }
 
 // ShowAPIEndpoint shows a specific API endpoint documentation
-func (h *HTTPHandler) ShowAPIEndpoint(c echo.Context, endpointPath string) error {
+func (h *HTTPHandler) ShowAPIEndpoint(c *echo.Context, endpointPath string) error {
 	// Check if user is logged in
 	isLoggedIn := false
 	if userID := c.Get("user_id"); userID != nil {
@@ -182,7 +183,7 @@ func (h *HTTPHandler) ShowAPIEndpoint(c echo.Context, endpointPath string) error
 }
 
 // showLegacyAPIEndpoint shows API endpoint documentation without explorer data
-func (h *HTTPHandler) showLegacyAPIEndpoint(c echo.Context, endpointPath string, isLoggedIn bool) error {
+func (h *HTTPHandler) showLegacyAPIEndpoint(c *echo.Context, endpointPath string, isLoggedIn bool) error {
 	endpoints := h.docs.GetAPIEndpoints()
 
 	// Find the endpoint
@@ -269,12 +270,12 @@ func (h *HTTPHandler) showLegacyAPIEndpoint(c echo.Context, endpointPath string,
 }
 
 // DocsHome redirects to the documentation index
-func (h *HTTPHandler) DocsHome(c echo.Context) error {
+func (h *HTTPHandler) DocsHome(c *echo.Context) error {
 	return c.Redirect(http.StatusFound, "/docs/index.md")
 }
 
 // APIHome shows the API documentation home page
-func (h *HTTPHandler) APIHome(c echo.Context) error {
+func (h *HTTPHandler) APIHome(c *echo.Context) error {
 	endpoints := h.docs.GetAPIEndpoints()
 	nav := h.docs.BuildNavigation()
 
@@ -343,7 +344,7 @@ func (h *HTTPHandler) APIHome(c echo.Context) error {
 }
 
 // Search searches through documentation
-func (h *HTTPHandler) Search(c echo.Context) error {
+func (h *HTTPHandler) Search(c *echo.Context) error {
 	query := c.QueryParam("q")
 	if query == "" {
 		return c.JSON(http.StatusBadRequest, map[string]string{
@@ -404,7 +405,7 @@ type SearchResult struct {
 }
 
 // TryEndpoint executes an API endpoint (for the interactive explorer)
-func (h *HTTPHandler) TryEndpoint(c echo.Context) error {
+func (h *HTTPHandler) TryEndpoint(c *echo.Context) error {
 	// This would execute the actual API request
 	// For now, return a placeholder
 	return c.JSON(http.StatusOK, map[string]interface{}{
@@ -413,7 +414,7 @@ func (h *HTTPHandler) TryEndpoint(c echo.Context) error {
 }
 
 // ServeSearchIndex serves the Lunr.js search index
-func (h *HTTPHandler) ServeSearchIndex(c echo.Context) error {
+func (h *HTTPHandler) ServeSearchIndex(c *echo.Context) error {
 	index, err := h.docs.GenerateSearchIndex()
 	if err != nil {
 		return c.JSON(http.StatusInternalServerError, map[string]string{