cli: rename profile v2 flag to --profile (#23883)

## Why

Profile v2 is taking over the user-facing profile selection path, so the
CLI no longer needs to expose the transitional `--profile-v2` spelling.
This switches the public args surface to `--profile` before the
remaining legacy profile plumbing is removed separately.

## What

- Rebind `--profile` and `-p` to the v2 profile name argument that
selects `$CODEX_HOME/<name>.config.toml`.
- Stop parsing the legacy shared CLI profile argument while keeping its
implementation path in place for follow-up cleanup.
- Update CLI validation, profile-name parse errors, and the
legacy-profile collision message/tests to refer to `--profile`.

## Testing

- `cargo test -p codex-cli -p codex-config -p codex-protocol -p
codex-utils-cli`

codex-rs/cli/src/main.rs

@@ -1477,7 +1477,7 @@ fn profile_v2_for_subcommand<'a>(
             subcommand: DebugSubcommand::PromptInput(_),
         }) => Ok(Some(profile_v2)),
         _ => anyhow::bail!(
-            "--profile-v2 only applies to runtime commands: `codex`, `codex exec`, `codex review`, `codex resume`, `codex fork`, and `codex debug prompt-input`."
+            "--profile only applies to runtime commands: `codex`, `codex exec`, `codex review`, `codex resume`, `codex fork`, and `codex debug prompt-input`."
         ),
     }
 }
@@ -2286,21 +2286,19 @@ mod tests {
 
     #[test]
     fn profile_v2_is_rejected_for_config_management_subcommands() {
-        assert!(
-            profile_v2_for_args(&["codex", "--profile-v2", "work", "features", "list"]).is_err()
-        );
+        assert!(profile_v2_for_args(&["codex", "--profile", "work", "features", "list"]).is_err());
     }
 
     #[test]
     fn profile_v2_is_allowed_for_runtime_subcommands() {
         assert_eq!(
-            profile_v2_for_args(&["codex", "--profile-v2", "work", "resume"])
+            profile_v2_for_args(&["codex", "--profile", "work", "resume"])
                 .expect("resume supports profile-v2")
                 .as_deref(),
             Some("work")
         );
         assert_eq!(
-            profile_v2_for_args(&["codex", "--profile-v2", "work", "debug", "prompt-input"])
+            profile_v2_for_args(&["codex", "--profile", "work", "debug", "prompt-input"])
                 .expect("debug prompt-input supports profile-v2")
                 .as_deref(),
             Some("work")
@@ -2310,8 +2308,7 @@ mod tests {
     #[test]
     fn profile_v2_rejects_non_plain_names_at_parse_time() {
         assert!(
-            MultitoolCli::try_parse_from(["codex", "--profile-v2", "nested/work", "resume"])
-                .is_err()
+            MultitoolCli::try_parse_from(["codex", "--profile", "nested/work", "resume"]).is_err()
         );
     }
 
@@ -2762,8 +2759,6 @@ mod tests {
                 "-m",
                 "gpt-5.1-test",
                 "-p",
-                "my-profile",
-                "--profile-v2",
                 "my-config",
                 "-C",
                 "/tmp",
@@ -2776,7 +2771,7 @@ mod tests {
 
         assert_eq!(interactive.model.as_deref(), Some("gpt-5.1-test"));
         assert!(interactive.oss);
-        assert_eq!(interactive.config_profile.as_deref(), Some("my-profile"));
+        assert_eq!(interactive.config_profile.as_deref(), None);
         assert_eq!(interactive.config_profile_v2.as_deref(), Some("my-config"));
         assert_matches!(
             interactive.sandbox_mode,

codex-rs/core/tests/suite/cli_stream.rs

@@ -196,9 +196,9 @@ async fn exec_cli_applies_model_instructions_file() {
     );
 }
 
-/// Verify that `codex exec --profile ...` preserves the active profile when it
-/// starts the in-process app-server thread, so profile-scoped
-/// `model_instructions_file` is applied to the outbound request.
+/// Verify that `codex exec --profile ...` preserves the active user config
+/// profile when it starts the in-process app-server thread, so the selected
+/// profile's `model_instructions_file` reaches the outbound request.
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
 async fn exec_cli_profile_applies_model_instructions_file() {
     skip_if_no_network!();
@@ -223,8 +223,8 @@ async fn exec_cli_profile_applies_model_instructions_file() {
 
     let home = TempDir::new().unwrap();
     std::fs::write(
-        home.path().join("config.toml"),
-        format!("[profiles.default]\nmodel_instructions_file = \"{custom_path_str}\"\n",),
+        home.path().join("default.config.toml"),
+        format!("model_instructions_file = \"{custom_path_str}\"\n"),
     )
     .unwrap();
 

codex-rs/protocol/src/config_types.rs

@@ -114,7 +114,7 @@ impl fmt::Display for ProfileV2NameParseError {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         write!(
             f,
-            "invalid --profile-v2 value `{}`; pass a plain name such as `work`",
+            "invalid --profile value `{}`; pass a plain name such as `work`",
             self.value
         )
     }

codex-rs/utils/cli/src/shared_options.rs

@@ -31,11 +31,11 @@ pub struct SharedCliOptions {
     pub oss_provider: Option<String>,
 
     /// Configuration profile from config.toml to specify default options.
-    #[arg(long = "profile", short = 'p')]
+    #[arg(skip)]
     pub config_profile: Option<String>,
 
     /// Layer $CODEX_HOME/<name>.config.toml on top of the base user config.
-    #[arg(long = "profile-v2")]
+    #[arg(long = "profile", short = 'p')]
     pub config_profile_v2: Option<ProfileV2Name>,
 
     /// Select the sandbox policy to use when executing model-generated shell