feat: item-attachments CRUD (#22)

* change /content/ -> /homebox/

* add cache to code generators

* update env variables to set data storage

* update env variables

* set env variables in prod container

* implement attachment post route (WIP)

* get attachment endpoint

* attachment download

* implement string utilities lib

* implement generic drop zone

* use explicit truncate

* remove clean dir

* drop strings composable for lib

* update item types and add attachments

* add attachment API

* implement service context

* consolidate API code

* implement editing attachments

* implement upload limit configuration

* improve error handling

* add docs for max upload size

* fix test cases

backend/internal/services/contexts.go

@@ -3,7 +3,8 @@ package services
 import (
 	"context"
 
-	"github.com/hay-kot/content/backend/internal/types"
+	"github.com/google/uuid"
+	"github.com/hay-kot/homebox/backend/internal/types"
 )
 
 type contextKeys struct {
@@ -15,6 +16,31 @@ var (
 	ContextUserToken = &contextKeys{name: "UserToken"}
 )
 
+type Context struct {
+	context.Context
+
+	// UID is a unique identifier for the acting user.
+	UID uuid.UUID
+
+	// GID is a unique identifier for the acting users group.
+	GID uuid.UUID
+
+	// User is the acting user.
+	User *types.UserOut
+}
+
+// NewContext is a helper function that returns the service context from the context.
+// This extracts the users from the context and embeds it into the ServiceContext struct
+func NewContext(ctx context.Context) Context {
+	user := UseUserCtx(ctx)
+	return Context{
+		Context: ctx,
+		UID:     user.ID,
+		GID:     user.GroupID,
+		User:    user,
+	}
+}
+
 // SetUserCtx is a helper function that sets the ContextUser and ContextUserToken
 // values within the context of a web request (or any context).
 func SetUserCtx(ctx context.Context, user *types.UserOut, token string) context.Context {