Fix GitHub Actions workflows to create virtual environment

Add uv venv step before installing dependencies in test and lint workflows

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: wshobson

.github/workflows/lint.yml

@@ -22,8 +22,12 @@ jobs:
     - name: Set up Python
       run: uv python install 3.12
 
+    - name: Create virtual environment
+      run: uv venv
+    
     - name: Install dependencies
       run: |
+        uv pip install -e .
         uv pip install --group dev
     
     - name: Run ruff

.github/workflows/test.yml

@@ -60,6 +60,9 @@ jobs:
         echo "TA_LIBRARY_PATH=C:\ta-lib\c\lib" >> $env:GITHUB_ENV
       shell: pwsh
 
+    - name: Create virtual environment
+      run: uv venv
+    
     - name: Install dependencies
       run: |
         uv pip install -e .