fix(workflow): use git stash --include-untracked to handle new untracked files

Plain `git stash` only stashes tracked modified files. Scripts like
track_recommendation_performance.py write new untracked files to
data/recommendations/ which block `git pull --rebase`. Adding
--include-untracked captures those files in the stash so the rebase
can proceed cleanly.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.github/workflows/daily-discovery.yml

@@ -91,7 +91,7 @@ jobs:
             echo "No new recommendations to commit"
           else
             git commit -m "chore: daily discovery ${{ steps.date.outputs.analysis_date }}"
-            git stash || true
+            git stash --include-untracked || true
             git pull --rebase origin ${{ github.ref_name }}
             git stash pop || true
             git push origin ${{ github.ref_name }}
@@ -112,7 +112,7 @@ jobs:
             echo "No performance updates"
           else
             git commit -m "chore: update performance tracking ${{ steps.date.outputs.analysis_date }}"
-            git stash || true
+            git stash --include-untracked || true
             git pull --rebase origin ${{ github.ref_name }}
             git stash pop || true
             git push origin ${{ github.ref_name }}
@@ -135,7 +135,7 @@ jobs:
             echo "No position updates"
           else
             git commit -m "chore: update positions ${{ steps.date.outputs.analysis_date }}"
-            git stash || true
+            git stash --include-untracked || true
             git pull --rebase origin ${{ github.ref_name }}
             git stash pop || true
             git push origin ${{ github.ref_name }}