fix: address all review findings (zero remaining)

Tests:
- Add WithTemperature tests (builder method, chaining, zero omission)
- Add temperature serialization tests (omitted when 0, included when set)

Composite action:
- Use python3 for robust JSON version parsing (replaces sed)
- Verify SHA-256 checksum before executing downloaded binary
- Wire up repo input (no longer hardcodes rodin/review-bot)

Release workflow:
- Handle 409 conflict (existing release for tag)
- Use file-based JSON parsing for reliability

Code:
- Tighten WithTemperature doc comment (single clear line)
- Fix flag alignment (missing tab on llmTemp declaration)

.gitea/workflows/release.yml

@@ -38,23 +38,34 @@ jobs:
           GITEA_URL="${{ github.server_url }}"
           REPO="${{ github.repository }}"
 
-          # Create release
-          RESPONSE=$(curl -sSf -X POST \
+          # Create release (or find existing one for this tag)
+          HTTP_CODE=$(curl -s -o /tmp/release_response.json -w "%{http_code}" -X POST \
             -H "Authorization: token ${GITEA_TOKEN}" \
             -H "Content-Type: application/json" \
             "${GITEA_URL}/api/v1/repos/${REPO}/releases" \
             -d "{\"tag_name\": \"${VERSION}\", \"name\": \"${VERSION}\", \"body\": \"Release ${VERSION}\", \"draft\": false, \"prerelease\": false}")
 
-          # Parse release ID using Python (robust JSON parsing)
-          RELEASE_ID=$(echo "$RESPONSE" | python3 -c "import sys, json; print(json.load(sys.stdin)['id'])")
-
-          if [ -z "$RELEASE_ID" ]; then
-            echo "Failed to create release" >&2
-            echo "$RESPONSE" >&2
+          if [ "$HTTP_CODE" = "409" ]; then
+            echo "Release for ${VERSION} already exists, fetching existing..."
+            curl -sSf -o /tmp/release_response.json \
+              -H "Authorization: token ${GITEA_TOKEN}" \
+              "${GITEA_URL}/api/v1/repos/${REPO}/releases/tags/${VERSION}"
+          elif [ "$HTTP_CODE" != "201" ]; then
+            echo "Failed to create release (HTTP ${HTTP_CODE})" >&2
+            cat /tmp/release_response.json >&2
             exit 1
           fi
 
-          echo "Created release ID: ${RELEASE_ID}"
+          # Parse release ID (python3 available on ubuntu-24.04 runners)
+          RELEASE_ID=$(python3 -c "import json; print(json.load(open('/tmp/release_response.json'))['id'])")
+
+          if [ -z "$RELEASE_ID" ]; then
+            echo "Failed to parse release ID" >&2
+            cat /tmp/release_response.json >&2
+            exit 1
+          fi
+
+          echo "Release ID: ${RELEASE_ID}"
 
           # Upload each asset
           for file in dist/*; do