feat: add vz run / vz stop for gpu-cli-style dev environments

Adds top-level `vz run <cmd>` that reads `vz.json`, boots a Linux VM via
the daemon, mounts the project directory via VirtioFS, and executes
commands inside the VM. The VM stays alive between runs (22ms warm exec)
until `vz stop`.

Stack changes:
- Proto: VolumeMount message + fields on CreateSandboxRequest
- Runtime contract: guest_path on StackVolumeMount
- Daemon: explicit mount support in sandbox creation, container bind mounts
- VM boot: kernel cmdline generation for mount target paths
- OCI bundle: skip host-side path creation for guest-only paths
- Release: build + sign + notarize vz-runtimed
- Install script: downloads vz-runtimed, version tracking, upgrade support

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: lightsofapollo

.github/workflows/release.yml

@@ -60,6 +60,7 @@ jobs:
         run: |
           cd crates
           cargo build --release -p vz-cli
+          cargo build --release -p vz-runtimed
           cargo build --release -p vz-guest-agent
 
       - name: Import code signing certificate
@@ -103,26 +104,50 @@ jobs:
           codesign --verify --verbose crates/target/release/vz
           echo "vz-cli signed successfully"
 
+      - name: Sign vz-runtimed with Developer ID
+        env:
+          APPLE_SIGNING_IDENTITY: ${{ secrets.APPLE_SIGNING_IDENTITY }}
+        run: |
+          codesign --sign "$APPLE_SIGNING_IDENTITY" \
+            --keychain "$KEYCHAIN_PATH" \
+            --entitlements entitlements/vz-cli.entitlements.plist \
+            --options runtime \
+            --timestamp \
+            --force \
+            crates/target/release/vz-runtimed
+
+          codesign --verify --verbose crates/target/release/vz-runtimed
+          echo "vz-runtimed signed successfully"
+
       - name: Sign vz-guest-agent (ad-hoc, no entitlements)
         run: |
           codesign --sign - --force crates/target/release/vz-guest-agent
           codesign --verify --verbose crates/target/release/vz-guest-agent
 
-      - name: Notarize vz-cli
+      - name: Notarize vz-cli and vz-runtimed
         env:
           APPLE_ID: ${{ secrets.APPLE_ID }}
           APPLE_APP_SPECIFIC_PASSWORD: ${{ secrets.APPLE_APP_SPECIFIC_PASSWORD }}
           APPLE_TEAM_ID: ${{ secrets.APPLE_TEAM_ID }}
         run: |
+          # Notarize vz-cli
           ditto -c -k --keepParent crates/target/release/vz vz-notarize.zip
-
           xcrun notarytool submit vz-notarize.zip \
             --apple-id "$APPLE_ID" \
             --password "$APPLE_APP_SPECIFIC_PASSWORD" \
             --team-id "$APPLE_TEAM_ID" \
             --wait
-
           rm vz-notarize.zip
+
+          # Notarize vz-runtimed
+          ditto -c -k --keepParent crates/target/release/vz-runtimed vz-runtimed-notarize.zip
+          xcrun notarytool submit vz-runtimed-notarize.zip \
+            --apple-id "$APPLE_ID" \
+            --password "$APPLE_APP_SPECIFIC_PASSWORD" \
+            --team-id "$APPLE_TEAM_ID" \
+            --wait
+          rm vz-runtimed-notarize.zip
+
           echo "Notarization complete"
 
       - name: Prepare release artifacts
@@ -136,6 +161,10 @@ jobs:
           chmod +x "dist/vz-v${VERSION}-darwin-arm64"
           shasum -a 256 "dist/vz-v${VERSION}-darwin-arm64" > "dist/vz-v${VERSION}-darwin-arm64.sha256"
 
+          cp crates/target/release/vz-runtimed "dist/vz-runtimed-v${VERSION}-darwin-arm64"
+          chmod +x "dist/vz-runtimed-v${VERSION}-darwin-arm64"
+          shasum -a 256 "dist/vz-runtimed-v${VERSION}-darwin-arm64" > "dist/vz-runtimed-v${VERSION}-darwin-arm64.sha256"
+
           cp crates/target/release/vz-guest-agent "dist/vz-guest-agent-v${VERSION}-darwin-arm64"
           chmod +x "dist/vz-guest-agent-v${VERSION}-darwin-arm64"
           shasum -a 256 "dist/vz-guest-agent-v${VERSION}-darwin-arm64" > "dist/vz-guest-agent-v${VERSION}-darwin-arm64.sha256"

crates/Cargo.lock

@@ -90,6 +90,7 @@ pub(crate) async fn try_create_sandbox_via_daemon(
         cpus: body.cpus.unwrap_or(0) as u32,
         memory_mb: body.memory_mb.unwrap_or(0),
         labels,
+        ..Default::default()
     };
 
     match client.create_sandbox_with_metadata(grpc_request).await {

crates/vz-api/src/daemon_bridge/sandbox.rs

@@ -1,6 +1,6 @@
 [package]
 name = "vz-cli"
-version = "0.1.0"
+version = "0.2.0"
 description = "CLI for managing containers and macOS VM sandboxes"
 edition.workspace = true
 rust-version.workspace = true