Fix smoke-test install: bust uv index cache on retry

The smoke-test jobs retry `uv pip install python-flexeval==<version>` to
absorb index propagation lag after publish. But uv caches the simple-index
listing on the first attempt, so when that attempt runs before the new
version has propagated, every subsequent retry reuses the stale cached
listing and fails with "no version of python-flexeval==<version>" — even
though the version is already live.

This is what failed smoke-test-pypi on the v0.5.1 release: 0.5.1 was fully
published (both files present on PyPI), but the job's 6 retries all saw the
cached pre-publish listing.

Add --refresh-package python-flexeval so each retry re-fetches that
package's index metadata (deps stay cached). Verified locally that a plain
install reproduced the stale-cache failure while --refresh-package resolved
0.5.1. Applied to both the PyPI and TestPyPI smoke jobs.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: levon003

.github/workflows/deploy-to-pypi.yml

@@ -114,12 +114,16 @@ jobs:
     - name: Install just-published build from PyPI into a clean venv
       # Install into a fresh venv (NOT the repo's env) so we exercise the
       # published wheel, not the source tree. The PyPI index can lag a few
-      # seconds behind publish, so retry the install.
+      # seconds behind publish, so retry the install. --refresh-package forces
+      # uv to re-fetch python-flexeval's index metadata on each attempt;
+      # otherwise uv caches the pre-publish listing and every retry sees the
+      # same stale "no such version" result.
       run: |
         uv venv /tmp/smoke-env
         version="${{ steps.version.outputs.version }}"
         for attempt in 1 2 3 4 5 6; do
           if uv pip install --python /tmp/smoke-env \
+              --refresh-package python-flexeval \
               "python-flexeval==${version}"; then
             break
           fi
@@ -206,11 +210,15 @@ jobs:
       # published wheel, not the source tree. Deps come from real PyPI; only
       # python-flexeval itself comes from TestPyPI. The TestPyPI simple index
       # can lag a few seconds behind publish, so retry the install.
+      # --refresh-package forces uv to re-fetch python-flexeval's index metadata
+      # on each attempt; otherwise uv caches the pre-publish listing and every
+      # retry sees the same stale "no such version" result.
       run: |
         uv venv /tmp/smoke-env
         version="${{ steps.version.outputs.version }}"
         for attempt in 1 2 3 4 5 6; do
           if uv pip install --python /tmp/smoke-env \
+              --refresh-package python-flexeval \
               --index-url https://test.pypi.org/simple/ \
               --extra-index-url https://pypi.org/simple/ \
               --index-strategy unsafe-best-match \