chore: add hot reload for development

- Makefile: add dev-backend (air) and dev-frontend (vite) targets
- backend/.air.toml: air config for Go live reload
- .gitignore: exclude backend/tmp/

backend/.air.toml

@@ -0,0 +1,38 @@
+# Air configuration for Go hot reload
+# Docs: https://github.com/air-verse/air
+
+root = "."
+tmp_dir = "tmp"
+
+[build]
+  bin = "./tmp/main"
+  cmd = "go build -o ./tmp/main ./cmd/openteam"
+  delay = 1000
+  exclude_dir = ["tmp", "vendor", "node_modules", "frontend"]
+  exclude_file = []
+  exclude_regex = ["_test.go", ".*_test.go"]
+  exclude_unchanged = false
+  follow_symlink = false
+  include_dir = []
+  include_ext = ["go", "tpl", "tmpl", "html", "sql"]
+  kill_delay = "0s"
+  log = "build-errors.log"
+  send_interrupt = false
+  stop_on_error = true
+
+[color]
+  build = "yellow"
+  main = "magenta"
+  runner = "green"
+  watcher = "cyan"
+
+[log]
+  main_only = false
+  time = false
+
+[misc]
+  clean_on_exit = false
+
+[screen]
+  clear_on_rebuild = false
+  keep_scroll = true