Remove unused code, update docs, and uniformize module file structure

README.md

@@ -30,13 +30,13 @@ and the repositories that need those dependencies.
 This project uses
 [`axum`] to handle incoming requests,
 [`reqwest`] to send requests to the GitHub API,
-[`git ls-remote`] to check the last commit on a remote branch,
+[`gix`] to check the latest commit on remote branches,
 and [`sqlx`] connected to a SQLite database to hold state.
 
 <!-- LINKS -->
 [`axum`]: https://docs.rs/axum/latest/axum/
 [`reqwest`]: https://docs.rs/reqwest/latest/reqwest/
-[`git ls-remote`]: https://git-scm.com/docs/git-ls-remote
+[`gix`]: https://docs.rs/gix/latest/gix/
 [`sqlx`]: https://docs.rs/sqlx/latest/sqlx/
 
 ## Usage

src/polling/error.rs

@@ -73,27 +73,10 @@ pub enum CommitHashError {
     #[error("Validation error: {0}")]
     Validation(#[from] ValidationError),
 
-    /// I/O error.
-    #[error("I/O error: {0}")]
-    Io(#[from] std::io::Error),
-
     /// Unexpected failure while fetching the commit hash.
     #[error("Unexpected failure while fetching the commit hash: {0}")]
     UnexpectedStatus(String),
 
-    /// Unexpected output while fetching the commit hash.
-    #[error(
-        "Unexpected output while fetching the commit hash. Repo: {repo_url}; Branch: {branch}; Output: {stdout}"
-    )]
-    UnexpectedOutput {
-        /// The unexpected output text.
-        stdout: String,
-        /// The relevant git repository URL.
-        repo_url: String,
-        /// The relevant git branch.
-        branch: String,
-    },
-
     /// Failed to find remote.
     #[error("Failed to find remote: {0}")]
     // Error is boxed because it is very large

src/trigger/error.rs

@@ -31,10 +31,6 @@ impl From<reqwest::Error> for WorkflowTriggerError {
 /// Authentication errors.
 #[derive(Debug, Error)]
 pub enum AuthError {
-    /// Failed to read PEM file.
-    #[error("Could not read PEM file: {0}")]
-    PemFile(#[from] std::io::Error),
-
     /// An error with time APIs.
     #[error("System time: {0}")]
     Time(#[from] std::time::SystemTimeError),