fix(release): install dependencies before merging macOS updater manifests

The 'Publish GitHub Release' job invokes scripts/merge-update-manifests.ts
which imports from @effect/platform-node. Without a prior bun install step
the release runner has no node_modules, so the script fails with:

  error: Cannot find module '@effect/platform-node/NodeServices' from
  /home/runner/work/t3code/t3code/scripts/merge-update-manifests.ts

Upstream's release job includes an 'Install dependencies' step between
Setup Node and Download artifacts (they run merge-update-manifests via
`node` too — same dep resolution requirement). Mirror that step in the
fork's simplified release flow.

Failed run: https://github.com/aaditagrawal/t3code/actions/runs/24624988376/job/72002885256

Author: aaditagrawal

.github/workflows/release.yml

@@ -246,6 +246,9 @@ jobs:
           node-version-file: package.json
           registry-url: https://registry.npmjs.org
 
+      - name: Install dependencies
+        run: bun install --frozen-lockfile
+
       - name: Download all desktop artifacts
         uses: actions/download-artifact@v8
         with: