Rename project from inventree to vibetree

- go.mod module path (and every internal/vibetree import) inventree -> vibetree
- cmd/inventree/ -> cmd/vibetree/, deploy/inventree.service -> vibetree.service
- Default site name (seed data + the siteName template func's fallback)
  is now "vibetree", shown in the navbar, <title>, and login page
- Session cookie renamed inventree_session -> vibetree_session
- Default DB path data/inventree.db -> data/vibetree.db, CLI/log text,
  Dockerfile, docker-compose.yml, README, .gitignore/.dockerignore all
  updated to match

Existing installs: this changes the session cookie name (users will be
signed out once) and the default DB filename (point -db at your existing
file, or rename it, to keep your data).

internal/auth/auth.go

@@ -10,12 +10,12 @@ import (
 	"net/http"
 	"time"
 
-	"inventree/internal/models"
-	"inventree/internal/users"
+	"vibetree/internal/models"
+	"vibetree/internal/users"
 )
 
 const (
-	CookieName   = "inventree_session"
+	CookieName   = "vibetree_session"
 	SessionTTL   = 7 * 24 * time.Hour
 	contextUserK = ctxKey("current_user")
 )