fix elb linker: remove runtime imports from el-install, add --clean, catch in dev/stage CI

el-install.el explicitly imported runtime/*.el modules (string, env, fs, exec,
json, http), which elb compiled to .c files in the shared dist/bin out_dir.
Linking those alongside el_runtime.c caused multiple definition errors for
every runtime function (http_get, http_patch, etc.). The runtime .el files are
thin wrappers over seed primitives already compiled into el_runtime.c — no
import needed.

Fixes:
- Remove all explicit runtime imports from el-install.el (root cause)
- Add --clean to every elb invocation in sdk-release.yaml so each build
  starts with a clean out_dir (defense-in-depth against stale .c files)
- Add elb build + epm/el-install build steps to ci-dev.yaml and ci-stage.yaml
  so linker errors are caught on every PR, not just stage->main

.gitea/workflows/ci-dev.yaml

@@ -174,6 +174,28 @@ jobs:
             -lcurl -lssl -lcrypto -lpthread -lm -o /tmp/el_native_fs
           /tmp/el_native_fs
 
+      # Build epm binary using elb (epm lives at repo root, not inside lang/)
+      - name: Build epm
+        run: |
+          ABS_ELB="$(pwd)/dist/bin/elb"
+          ABS_ELC="$(pwd)/dist/platform/elc"
+          ABS_RUNTIME="$(pwd)/el-compiler/runtime"
+          ABS_OUT="$(pwd)/dist/bin"
+          (cd ../epm && "$ABS_ELB" --clean --elc="$ABS_ELC" --runtime="$ABS_RUNTIME" --out="$ABS_OUT")
+          chmod +x dist/bin/epm
+          echo "epm built"
+
+      # Build el-install binary using elb
+      - name: Build el-install
+        run: |
+          ABS_ELB="$(pwd)/dist/bin/elb"
+          ABS_ELC="$(pwd)/dist/platform/elc"
+          ABS_RUNTIME="$(pwd)/el-compiler/runtime"
+          ABS_OUT="$(pwd)/dist/bin"
+          (cd tools/install && "$ABS_ELB" --clean --elc="$ABS_ELC" --runtime="$ABS_RUNTIME" --out="$ABS_OUT")
+          chmod +x dist/bin/el-install
+          echo "el-install built"
+
       # Publish only after merge (push event), not on PR validation runs
       - name: Publish El SDK to Artifact Registry (dev)
         if: github.event_name == 'push'