fix(ci): namespace node_modules artifact names by build_name to prevent conflicts (#27599)

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## **Description**

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When multiple `build.yml` invocations run in parallel within the same
workflow run (e.g. nightly builds triggering `main-exp` and `main-rc`
simultaneously), the `setup-dependencies` job uploads node_modules
tarballs as artifacts named `node-modules-{platform}`. Since GitHub
Actions requires unique artifact names per workflow run, the second
upload fails with a `409 Conflict`.

This PR namespaces the artifact name by including `build_name`, changing
from `node-modules-{platform}` to
`node-modules-{build_name}-{platform}`. This produces unique names like
`node-modules-main-exp-android` and `node-modules-main-rc-android`,
allowing parallel invocations to coexist. The tarball filename inside
the artifact remains unchanged (`node-modules-{platform}.tar.gz`), so
the extract step requires no modification.

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## **Related issues**

Fixes:

## **Manual testing steps**

N/A -- CI-only change. Verified by triggering a nightly build that
invokes `build.yml` twice in parallel (main-exp + main-rc) and
confirming both setup-dependencies jobs succeed without artifact name
conflicts.

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### **Before**

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### **After**

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Made with [Cursor](https://cursor.com)

<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> **Low Risk**
> Low risk CI-only change that just adjusts artifact naming to avoid
collisions when multiple `build.yml` invocations run in the same
workflow run.
> 
> **Overview**
> Prevents GitHub Actions artifact upload/download name collisions when
`build.yml` runs concurrently for different `build_name` values.
> 
> The `setup-dependencies` job now uploads `node_modules` tarballs with
`build_name` included (e.g., `node-modules-${{ inputs.build_name }}-${{
matrix.platform }}`), and the `build` job downloads artifacts using the
same names; the tarball filename inside the artifact remains unchanged.
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
149822e. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

Author: tommasini

.github/workflows/build.yml

@@ -115,7 +115,7 @@ jobs:
       build_name: ${{ inputs.build_name }}
       use-tarball: true
       upload-artifact: true
-      artifact-name: node-modules-${{ matrix.platform }}
+      artifact-name: node-modules-${{ inputs.build_name }}-${{ matrix.platform }}
       artifact-retention-days: 1
 
   # Build
@@ -165,7 +165,7 @@ jobs:
       - name: Download node_modules tarball
         uses: actions/download-artifact@v4
         with:
-          name: node-modules-${{ matrix.platform }}
+          name: node-modules-${{ inputs.build_name }}-${{ matrix.platform }}
 
       - name: Extract tarball (preserves symlinks)
         run: |