Stop shipping codex-exec-server in release artifacts (#57628)

## What changed

- Remove the standalone executor from CLI and app-server packages, release binary lists, and Bazel runtime archives.
- Remove the package builder's `--exec-server-bin` option and `execServer` metadata, along with executor-specific installer checks, signing configuration, and package smoke tests.
- Keep the standalone executor available to build from source.

GitOrigin-RevId: ada4c92c092e3c7a3067129913e99f4606f7adc8

scripts/codex_package/cargo.py

@@ -18,7 +18,6 @@ CODEX_RS_ROOT = REPO_ROOT / "codex-rs"
 class SourceBuildOutputs:
     entrypoint_bin: Path
     code_mode_host_bin: Path
-    exec_server_bin: Path
     bwrap_bin: Path | None
     codex_command_runner_bin: Path | None
     codex_windows_sandbox_setup_bin: Path | None
@@ -32,7 +31,6 @@ def build_source_binaries(
     profile: str,
     entrypoint_bin: Path | None,
     code_mode_host_bin: Path | None,
-    exec_server_bin: Path | None,
     bwrap_bin: Path | None,
     codex_command_runner_bin: Path | None,
     codex_windows_sandbox_setup_bin: Path | None,
@@ -48,7 +46,6 @@ def build_source_binaries(
         variant,
         build_entrypoint=entrypoint_bin is None,
         build_code_mode_host=code_mode_host_bin is None,
-        build_exec_server=exec_server_bin is None,
         build_bwrap=spec.is_linux and bwrap_bin is None,
         build_codex_command_runner=spec.is_windows and codex_command_runner_bin is None,
         build_codex_windows_sandbox_setup=spec.is_windows
@@ -67,11 +64,7 @@ def build_source_binaries(
             cmd.extend(["--bin", binary])
 
         cargo_env = None
-        if (
-            entrypoint_bin is None
-            or code_mode_host_bin is None
-            or exec_server_bin is None
-        ):
+        if entrypoint_bin is None or code_mode_host_bin is None:
             codex_v8_env = resolve_codex_v8_cargo_env(spec)
             if codex_v8_env:
                 cargo_env = {**os.environ, **codex_v8_env}
@@ -95,11 +88,6 @@ def build_source_binaries(
             if code_mode_host_bin is not None
             else output_dir / f"codex-code-mode-host{spec.exe_suffix}"
         ),
-        exec_server_bin=(
-            exec_server_bin.resolve()
-            if exec_server_bin is not None
-            else output_dir / f"codex-exec-server{spec.exe_suffix}"
-        ),
         bwrap_bin=resolve_output_path(
             bwrap_bin,
             output_dir / "bwrap" if spec.is_linux else None,
@@ -123,7 +111,6 @@ def source_binaries_for_target(
     *,
     build_entrypoint: bool,
     build_code_mode_host: bool,
-    build_exec_server: bool,
     build_bwrap: bool,
     build_codex_command_runner: bool,
     build_codex_windows_sandbox_setup: bool,
@@ -133,8 +120,6 @@ def source_binaries_for_target(
         binaries.append(variant.cargo_bin)
     if build_code_mode_host:
         binaries.append("codex-code-mode-host")
-    if build_exec_server:
-        binaries.append("codex-exec-server")
     if build_bwrap:
         binaries.append("bwrap")
     if build_codex_command_runner:
@@ -201,7 +186,6 @@ def validate_source_outputs(outputs: SourceBuildOutputs) -> None:
     for path in [
         outputs.entrypoint_bin,
         outputs.code_mode_host_bin,
-        outputs.exec_server_bin,
         outputs.bwrap_bin,
         outputs.codex_command_runner_bin,
         outputs.codex_windows_sandbox_setup_bin,