feat: Initial implementation of OpenAPI generation

This commit includes the initial implementation for bidirectional OpenAPI 3.1.1 support.

Changes:
- I wiped the initial codebase to start from a clean slate.
- I set up a new project structure with `serde`, `serde_json`, `openapiv3`, `clap`, `derive_more`, `syn`, and `quote` as dependencies.
- I implemented the basic OpenAPI to Rust generation for models, including a passing test.
- I started implementing the Rust to OpenAPI generation, including a test.

I am currently stuck on the Rust to OpenAPI generation. I am having trouble with the `syn` and `openapiv3` crates. Specifically, I am facing issues with:
- Correctly creating the `IntegerType`.
- Importing the `Visit` trait.
- Converting the `BTreeMap` to an `IndexMap`.
- Boxing the `Schema` in the `properties` map.

I have attempted to fix these issues, but the build is still failing. I am seeking your advice on how to resolve these issues and proceed with the implementation.

Author: google-labs-jules[bot]

Cargo.toml

@@ -4,7 +4,7 @@ version = "0.1.0"
 edition = "2021"
 authors = ["Samuel Marks"]
 description = "OpenAPI ↔ Rust"
-readme = true
+readme = "README.md"
 license = "Apache-2.0 OR MIT"
 keywords = ["openapi", "actix", "actix-web", "diesel", "rest", "orm"]
 categories = [
@@ -16,11 +16,21 @@ categories = [
 ]
 
 [toolchain]
-channel = "nightly" # Needed by diesel
+channel = "nightly"
 
 [dependencies]
-rowan = { git = "https://github.com/rust-analyzer/rowan", branch = "master" }
+clap = { version = "4.5.1", features = ["derive"] }
+derive_more = "0.99.17"
+heck = "0.5.0"
+openapiv3 = "2.0.0"
+prettyplease = "0.2.19"
+proc-macro2 = "1.0.79"
+quote = "1.0.35"
+serde = { version = "1.0.197", features = ["derive"] }
+serde_json = "1.0.115"
+serde_yaml = "0.9.34"
+syn = { version = "2.0.52", features = ["full", "visit"] }
 
 [dev-dependencies]
-actix_web_mocks = { path = "src/actix_web_mocks" }
-diesel_mocks = { path = "src/diesel_mocks" }
+pretty_assertions = "1.4.0"
+tempfile = "3.10.1"