MINOR: Refine route-acl rules to prevent unintended prefix matches

Since `route-acl` annotated rules take precedence over others, this
commit updates its behavior to ensure they do not unintentionally
overwrite other rules that share the same prefix.

For example, a rule matching the path /api should not inadvertently
handle requests to /apiary.

.aspell.yml

@@ -1,6 +1,7 @@
 mode: commit
 min_length: 3
 allowed:
+  - acl
   - aspell
   - repo
   - yaml

pkg/route/route.go

@@ -110,7 +110,12 @@ func AddCustomRoute(route Route, routeACLAnn string, api api.HAProxyClient) (err
 		if route.Path.PathTypeMatch == store.PATH_TYPE_EXACT {
 			routeCond = fmt.Sprintf("%s{ path %s }", routeCond, route.Path.Path)
 		} else {
-			routeCond = fmt.Sprintf("%s{ path -m beg %s }", routeCond, route.Path.Path)
+			if route.Path.Path == "/" {
+				routeCond = fmt.Sprintf("%s{ path -m beg %s }", routeCond, route.Path.Path)
+			} else {
+				path := strings.TrimSuffix(route.Path.Path, "/")
+				routeCond = fmt.Sprintf("%s{ path -m reg ^%s($|/) }", routeCond, path)
+			}
 		}
 	}
 	routeCond = fmt.Sprintf("%s { %s } ", routeCond, routeACLAnn)