feat: Run cargo shear during CI (#3338)

Run cargo shear as part of the CI to ensure no unused dependencies

codex-rs/core/Cargo.toml

@@ -26,14 +26,12 @@ eventsource-stream = "0.2.3"
 futures = "0.3"
 libc = "0.2.175"
 mcp-types = { path = "../mcp-types" }
-mime_guess = "2.0"
 os_info = "3.12.0"
 portable-pty = "0.9.0"
 rand = "0.9"
 regex-lite = "0.1.7"
 reqwest = { version = "0.12", features = ["json", "stream"] }
 serde = { version = "1", features = ["derive"] }
-serde_bytes = "0.11"
 serde_json = "1"
 sha1 = "0.10.6"
 shlex = "1.3.0"
@@ -56,7 +54,6 @@ tracing = { version = "0.1.41", features = ["log"] }
 tree-sitter = "0.25.9"
 tree-sitter-bash = "0.25.0"
 uuid = { version = "1", features = ["serde", "v4"] }
-whoami = "1.6.1"
 wildmatch = "2.4.0"
 
 
@@ -85,3 +82,6 @@ tempfile = "3"
 tokio-test = "0.4"
 walkdir = "2.5.0"
 wiremock = "0.6"
+
+[package.metadata.cargo-shear]
+ignored = ["openssl-sys"]