Add remote server cross compilation (#19136)

This will allow us to compile debug builds of the remote-server for a
different architecture than the one we are developing on.

This also adds a CI step for building our remote server with minimal
dependencies.

Release Notes:

- N/A

.github/workflows/ci.yml

@@ -99,7 +99,10 @@ jobs:
         run: cargo build -p collab
 
       - name: Build other binaries and features
-        run: cargo build --workspace --bins --all-features; cargo check -p gpui --features "macos-blade"
+        run: |
+          cargo build --workspace --bins --all-features
+          cargo check -p gpui --features "macos-blade"
+          cargo build -p remote_server
 
   linux_tests:
     timeout-minutes: 60
@@ -133,6 +136,32 @@ jobs:
       - name: Build Zed
         run: cargo build -p zed
 
+  build_remote_server:
+    timeout-minutes: 60
+    name: (Linux) Build Remote Server
+    runs-on:
+      - buildjet-16vcpu-ubuntu-2204
+    steps:
+      - name: Add Rust to the PATH
+        run: echo "$HOME/.cargo/bin" >> $GITHUB_PATH
+
+      - name: Checkout repo
+        uses: actions/checkout@eef61447b9ff4aafe5dcd4e0bbf5d482be7e7871 # v4
+        with:
+          clean: false
+
+      - name: Cache dependencies
+        uses: swatinem/rust-cache@23bce251a8cd2ffc3c1075eaa2367cf899916d84 # v2
+        with:
+          save-if: ${{ github.ref == 'refs/heads/main' }}
+          cache-provider: "buildjet"
+
+      - name: Install Clang & Mold
+        run: ./script/remote-server && ./script/install-mold 2.34.0
+
+      - name: Build Remote Server
+        run: cargo build -p remote_server
+
   # todo(windows): Actually run the tests
   windows_tests:
     timeout-minutes: 60