Add .env to .gitignore and update dependencies

- Added .env file to .gitignore to prevent environment secrets from being tracked.
- Updated Cargo.lock to include new dependencies: mime, mime_guess, and unicase.
- Modified Cargo.toml to enable multipart feature for reqwest.
- Introduced a new PowerShell script for building and publishing the Rojo plugin.
- Removed deprecated auth_cookie.rs file and adjusted upload command for new upload methods.

Cargo.lock

@@ -1810,6 +1810,22 @@ dependencies = [
  "tempfile",
 ]
 
+[[package]]
+name = "mime"
+version = "0.3.17"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6877bb514081ee2a7ff5ef9de3281f14a4dd4bceac4c09388074a6b5df8a139a"
+
+[[package]]
+name = "mime_guess"
+version = "2.0.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f7c44f8e672c00fe5308fa235f821cb4198414e1c77935c1ab6948d3fd78550e"
+dependencies = [
+ "mime",
+ "unicase",
+]
+
 [[package]]
 name = "miniz_oxide"
 version = "0.8.9"
@@ -2545,6 +2561,7 @@ dependencies = [
  "hyper-util",
  "js-sys",
  "log",
+ "mime_guess",
  "percent-encoding",
  "pin-project-lite",
  "quinn",
@@ -3617,6 +3634,12 @@ version = "0.1.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2896d95c02a80c6d6a5d6e953d479f5ddf2dfdb6a244441010e373ac0fb88971"
 
+[[package]]
+name = "unicase"
+version = "2.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dbc4bc3a9f746d862c45cb89d705aa10f187bb96c76001afab07a0d35ce60142"
+
 [[package]]
 name = "unicode-ident"
 version = "1.0.23"