[codex] Restore release symbol artifacts with line tables (#26202)

## Summary

- Restore separate release symbol archives for macOS, Linux, and Windows
binaries.
- Build release binaries with `line-tables-only` debuginfo instead of
full debuginfo.
- Strip Unix distribution binaries after extracting symbols, preserve
Windows PDBs, and keep symbol archives available to the release job.
- Strip the packaged Linux `bwrap` binary before hashing it so the
embedded digest matches the distributed bytes.

## Root cause

The first symbol-artifact implementation enabled
`CARGO_PROFILE_RELEASE_DEBUG=full`. In the June 2 release runs, macOS
ARM primary builds reached the 90-minute timeout while still inside
`Cargo build`. After the symbol changes were reverted, the same primary
build completed in about 22 minutes. The archive step itself completed
in tens of seconds when reached.

Rust's `line-tables-only` debuginfo level preserves function names and
source locations for symbolication without emitting the heavier variable
and type information from full debuginfo.

## Validation

- Ran `just fmt` from `codex-rs`.
- Ran `just test-github-scripts` from the repository root: 23 tests
passed.
- Ran `bash -n` and `shellcheck` on
`.github/scripts/archive-release-symbols-and-strip-binaries.sh`.
- Parsed both modified workflows as YAML and ran `git diff --check`.
- Built a macOS release smoke binary with `line-tables-only`, archived
its dSYM through the restored script, stripped the production binary,
and verified that `atos` resolves `symbol_smoke_function` to
`main.rs:2`.
- Ran Linux archive-script control-flow coverage with stubbed `objcopy`
and `strip` commands.
- Ran Windows PDB archive staging coverage and verified
underscore-emitted Rust PDB names are staged under shipped hyphenated
binary names.

## Follow-up

The release workflow only runs for tags or manual dispatches, so CI
cannot dry-run the full release matrix on this PR. The next release run
will verify runner time and memory behavior under `line-tables-only`.

.github/scripts/archive-release-symbols-and-strip-binaries.sh

@@ -0,0 +1,119 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+usage() {
+  cat <<'EOF'
+Usage: archive-release-symbols-and-strip-binaries.sh \
+  --target <rust-target> \
+  --artifact-name <artifact-name> \
+  --release-dir <dir> \
+  --archive-dir <dir> \
+  --binaries "<space-delimited binary basenames>"
+EOF
+}
+
+target=""
+artifact_name=""
+release_dir=""
+archive_dir=""
+binaries=""
+
+while [[ $# -gt 0 ]]; do
+  case "$1" in
+    --target)
+      target="${2:?--target requires a value}"
+      shift 2
+      ;;
+    --artifact-name)
+      artifact_name="${2:?--artifact-name requires a value}"
+      shift 2
+      ;;
+    --release-dir)
+      release_dir="${2:?--release-dir requires a value}"
+      shift 2
+      ;;
+    --archive-dir)
+      archive_dir="${2:?--archive-dir requires a value}"
+      shift 2
+      ;;
+    --binaries)
+      binaries="${2:?--binaries requires a value}"
+      shift 2
+      ;;
+    -h|--help)
+      usage
+      exit 0
+      ;;
+    *)
+      echo "Unexpected argument: $1" >&2
+      usage >&2
+      exit 1
+      ;;
+  esac
+done
+
+if [[ -z "$target" || -z "$artifact_name" || -z "$release_dir" || -z "$archive_dir" || -z "$binaries" ]]; then
+  usage >&2
+  exit 1
+fi
+
+symbols_root="${RUNNER_TEMP:-/tmp}/codex-symbols-${artifact_name}"
+symbols_dir="${symbols_root}/codex-symbols-${artifact_name}"
+archive_path="${archive_dir%/}/codex-symbols-${artifact_name}.tar.gz"
+rm -rf "$symbols_root"
+mkdir -p "$symbols_dir" "$archive_dir"
+read -r -a binary_names <<< "$binaries"
+
+case "$target" in
+  *apple-darwin)
+    for binary in "${binary_names[@]}"; do
+      binary_path="${release_dir%/}/${binary}"
+      dsym_path="${binary_path}.dSYM"
+      if [[ ! -f "$binary_path" ]]; then
+        echo "Binary $binary_path not found" >&2
+        exit 1
+      fi
+      if [[ ! -d "$dsym_path" ]]; then
+        echo "dSYM $dsym_path not found" >&2
+        exit 1
+      fi
+
+      cp -RL "$dsym_path" "${symbols_dir}/${binary}.dSYM"
+      strip -S -x "$binary_path"
+    done
+    ;;
+  *linux*)
+    objcopy_bin="${OBJCOPY:-objcopy}"
+    strip_bin="${STRIP:-strip}"
+    for binary in "${binary_names[@]}"; do
+      binary_path="${release_dir%/}/${binary}"
+      debug_path="${symbols_dir}/${binary}.debug"
+      if [[ ! -f "$binary_path" ]]; then
+        echo "Binary $binary_path not found" >&2
+        exit 1
+      fi
+
+      "$objcopy_bin" --only-keep-debug "$binary_path" "$debug_path"
+      "$strip_bin" --strip-debug --strip-unneeded "$binary_path"
+      "$objcopy_bin" --add-gnu-debuglink="$debug_path" "$binary_path"
+    done
+    ;;
+  *windows*)
+    for binary in "${binary_names[@]}"; do
+      pdb_path="${release_dir%/}/${binary}.pdb"
+      if [[ ! -f "$pdb_path" ]]; then
+        echo "PDB $pdb_path not found" >&2
+        exit 1
+      fi
+
+      cp "$pdb_path" "${symbols_dir}/${binary}.pdb"
+    done
+    ;;
+  *)
+    echo "No symbols packaging support for target: $target" >&2
+    exit 1
+    ;;
+esac
+
+rm -f "$archive_path"
+tar -C "$symbols_root" -czf "$archive_path" "codex-symbols-${artifact_name}"