fix: upgrade setup-uv@v5 → v8 (Node.js 24 native), add uv.lock

- setup-uv@v8 runs on Node.js 24 natively — no more deprecation warnings
- Removed FORCE_JAVASCRIPT_ACTIONS_TO_NODE24 workaround (no longer needed)
- Added uv.lock for reproducible dependency resolution

.github/workflows/ci.yml

@@ -6,9 +6,6 @@ on:
   pull_request:
     branches: [main]
 
-env:
-  FORCE_JAVASCRIPT_ACTIONS_TO_NODE24: true
-
 jobs:
   test:
     runs-on: ubuntu-latest
@@ -20,7 +17,7 @@ jobs:
           python-version: "3.13"
 
       - name: Install uv
-        uses: astral-sh/setup-uv@v5
+        uses: astral-sh/setup-uv@v8
 
       - name: Install dependencies
         run: uv pip install --system ".[dev]"

.github/workflows/deploy.yml

@@ -4,9 +4,6 @@ on:
   push:
     branches: [main]
 
-env:
-  FORCE_JAVASCRIPT_ACTIONS_TO_NODE24: true
-
 jobs:
   test:
     runs-on: ubuntu-latest
@@ -18,7 +15,7 @@ jobs:
           python-version: "3.13"
 
       - name: Install uv
-        uses: astral-sh/setup-uv@v5
+        uses: astral-sh/setup-uv@v8
 
       - name: Install dependencies
         run: uv pip install --system ".[dev]"