chore: introduce codex-common crate (#843)

I started this PR because I wanted to share the `format_duration()`
utility function in `codex-rs/exec/src/event_processor.rs` with the TUI.
The question was: where to put it?

`core` should have as few dependencies as possible, so moving it there
would introduce a dependency on `chrono`, which seemed undesirable.
`core` already had this `cli` feature to deal with a similar situation
around sharing common utility functions, so I decided to:

* make `core` feature-free
* introduce `common`
* `common` can have as many "special interest" features as it needs,
each of which can declare their own deps
* the first two features of common are `cli` and `elapsed`

In practice, this meant updating a number of `Cargo.toml` files,
replacing this line:

```toml
codex-core = { path = "../core", features = ["cli"] }
```

with these:

```toml
codex-core = { path = "../core" }
codex-common = { path = "../common", features = ["cli"] }
```

Moving `format_duration()` into its own file gave it some "breathing
room" to add a unit test, so I had Codex generate some tests and new
support for durations over 1 minute.

codex-rs/core/Cargo.toml

@@ -56,9 +56,3 @@ assert_cmd = "2"
 predicates = "3"
 tempfile = "3"
 wiremock = "0.6"
-
-[features]
-default = []
-
-# Separate feature so that `clap` is not a mandatory dependency.
-cli = ["clap"]

codex-rs/core/src/approval_mode_cli_arg.rs

@@ -1,73 +0,0 @@
-//! Standard type to use with the `--approval-mode` CLI option.
-//! Available when the `cli` feature is enabled for the crate.
-
-use clap::ArgAction;
-use clap::Parser;
-use clap::ValueEnum;
-
-use crate::config::parse_sandbox_permission_with_base_path;
-use crate::protocol::AskForApproval;
-use crate::protocol::SandboxPermission;
-
-#[derive(Clone, Copy, Debug, ValueEnum)]
-#[value(rename_all = "kebab-case")]
-pub enum ApprovalModeCliArg {
-    /// Run all commands without asking for user approval.
-    /// Only asks for approval if a command fails to execute, in which case it
-    /// will escalate to the user to ask for un-sandboxed execution.
-    OnFailure,
-
-    /// Only run "known safe" commands (e.g. ls, cat, sed) without
-    /// asking for user approval. Will escalate to the user if the model
-    /// proposes a command that is not allow-listed.
-    UnlessAllowListed,
-
-    /// Never ask for user approval
-    /// Execution failures are immediately returned to the model.
-    Never,
-}
-
-impl From<ApprovalModeCliArg> for AskForApproval {
-    fn from(value: ApprovalModeCliArg) -> Self {
-        match value {
-            ApprovalModeCliArg::OnFailure => AskForApproval::OnFailure,
-            ApprovalModeCliArg::UnlessAllowListed => AskForApproval::UnlessAllowListed,
-            ApprovalModeCliArg::Never => AskForApproval::Never,
-        }
-    }
-}
-
-#[derive(Parser, Debug)]
-pub struct SandboxPermissionOption {
-    /// Specify this flag multiple times to specify the full set of permissions
-    /// to grant to Codex.
-    ///
-    /// ```shell
-    /// codex -s disk-full-read-access \
-    ///       -s disk-write-cwd \
-    ///       -s disk-write-platform-user-temp-folder \
-    ///       -s disk-write-platform-global-temp-folder
-    /// ```
-    ///
-    /// Note disk-write-folder takes a value:
-    ///
-    /// ```shell
-    ///     -s disk-write-folder=$HOME/.pyenv/shims
-    /// ```
-    ///
-    /// These permissions are quite broad and should be used with caution:
-    ///
-    /// ```shell
-    ///     -s disk-full-write-access
-    ///     -s network-full-access
-    /// ```
-    #[arg(long = "sandbox-permission", short = 's', action = ArgAction::Append, value_parser = parse_sandbox_permission)]
-    pub permissions: Option<Vec<SandboxPermission>>,
-}
-
-/// Custom value-parser so we can keep the CLI surface small *and*
-/// still handle the parameterised `disk-write-folder` case.
-fn parse_sandbox_permission(raw: &str) -> std::io::Result<SandboxPermission> {
-    let base_path = std::env::current_dir()?;
-    parse_sandbox_permission_with_base_path(raw, base_path)
-}

codex-rs/core/src/config.rs

@@ -266,7 +266,7 @@ pub fn log_dir() -> std::io::Result<PathBuf> {
     Ok(p)
 }
 
-pub(crate) fn parse_sandbox_permission_with_base_path(
+pub fn parse_sandbox_permission_with_base_path(
     raw: &str,
     base_path: PathBuf,
 ) -> std::io::Result<SandboxPermission> {

codex-rs/core/src/lib.rs

@@ -26,10 +26,3 @@ pub mod util;
 mod zdr_transcript;
 
 pub use codex::Codex;
-
-#[cfg(feature = "cli")]
-mod approval_mode_cli_arg;
-#[cfg(feature = "cli")]
-pub use approval_mode_cli_arg::ApprovalModeCliArg;
-#[cfg(feature = "cli")]
-pub use approval_mode_cli_arg::SandboxPermissionOption;