fix(P1): release job uses existing bin/orca from build job

The release job's go build fails due to disk full (CoreCI's SQLite
logging fills the disk during go test -race). The build job already
builds bin/orca successfully — the release job should just package it
and upload. Only rebuild if bin/orca doesn't exist.

---ci---
project: orca
phase: 1
milestone: v0.16
status: execute
---/ci---

scripts/ci-run.sh

@@ -109,30 +109,24 @@ case "$JOB" in
 
     info "release ${VERSION} — GITEA_TOKEN length: ${#GITEA_TOKEN}"
 
-    # Clean up disk space — CoreCI's SQLite logging can fill the disk.
-    # Remove coverage.out and Go build cache to free space.
+    # Clean up disk space — CoreCI's SQLite logging fills the disk.
     rm -f coverage.out 2>/dev/null || true
     go clean -cache 2>/dev/null || true
 
-    # Rebuild the binary (the build job's binary may not persist if the
-    # executor uses separate workdirs, or the disk was full).
-    info "building release binary..."
-    GIT_COMMIT="${CI_COMMIT_SHA:-unknown}"
-    BUILD_TIME="$(date -u +%Y-%m-%dT%H:%M:%SZ)"
-    LDFLAGS="-s -w \
-      -X git.cloudinit.dev/coreci/orca/internal/cli.version=${VERSION} \
-      -X git.cloudinit.dev/coreci/orca/internal/cli.gitCommit=${GIT_COMMIT} \
-      -X git.cloudinit.dev/coreci/orca/internal/cli.buildTime=${BUILD_TIME}"
-    mkdir -p bin
-    go build -trimpath -ldflags="${LDFLAGS}" -o bin/orca ./cmd/orca 2>&1
-    BUILD_EXIT=$?
-    if [ ${BUILD_EXIT} -ne 0 ]; then
-      info "go build failed (exit ${BUILD_EXIT}) — trying with existing bin/orca from build job"
-      if [ -x bin/orca ]; then
-        info "found existing bin/orca from build job"
-      else
-        err "go build failed and no existing binary found"
-      fi
+    # Use the binary built by the 'build' job (it shares the same workdir).
+    # Rebuild only if the binary doesn't exist.
+    if [ ! -x bin/orca ]; then
+      info "bin/orca not found — rebuilding..."
+      GIT_COMMIT="${CI_COMMIT_SHA:-unknown}"
+      BUILD_TIME="$(date -u +%Y-%m-%dT%H:%M:%SZ)"
+      LDFLAGS="-s -w \
+        -X git.cloudinit.dev/coreci/orca/internal/cli.version=${VERSION} \
+        -X git.cloudinit.dev/coreci/orca/internal/cli.gitCommit=${GIT_COMMIT} \
+        -X git.cloudinit.dev/coreci/orca/internal/cli.buildTime=${BUILD_TIME}"
+      mkdir -p bin
+      go build -trimpath -ldflags="${LDFLAGS}" -o bin/orca ./cmd/orca 2>&1 || err "go build failed"
+    else
+      info "using existing bin/orca from build job"
     fi
     tar -czf "${TARBALL}" -C bin orca 2>&1 || err "tar failed"
     sha256sum "${TARBALL}" > SHA256SUMS 2>&1 || err "sha256sum failed"