Bot: quote the response_format JSON for --argjson

--argjson requires strict JSON; the unquoted-key object made jq fail,
sent an empty request body, and the triage died with 'model returned
nothing'. Also log the raw API response when choices is missing so the
next failure shows its cause immediately.

.github/scripts/bot.sh

@@ -25,17 +25,23 @@ repo="$GITHUB_REPOSITORY"
 
 ask_model() { # $1 = system prompt, $2 = user payload, $3 = "json" for JSON mode; prints the answer
   local body="${2:0:$MAX_CHARS}" extra
-  local req
+  local req resp
   extra='{}'
-  [ "${3:-}" = "json" ] && extra='{response_format: {type: "json_object"}}'
+  [ "${3:-}" = "json" ] && extra='{ "response_format": { "type": "json_object" } }'
   req=$(jq -n --arg sys "$1" --arg body "$body" --argjson extra "$extra" \
     '{model: "deepseek-flash",
       messages: [{role: "system", content: $sys}, {role: "user", content: $body}],
       max_tokens: 900, temperature: 0} * $extra')
-  curl -sS --max-time 120 https://api.deepseek.com/chat/completions \
+  resp=$(curl -sS --max-time 120 https://api.deepseek.com/chat/completions \
     -H "Authorization: Bearer $DEEPSEEK_API_KEY" \
     -H 'Content-Type: application/json' \
-    -d "$req" | jq -r '.choices[0].message.content // empty'
+    -d "$req")
+  if ! jq -e '.choices[0].message.content' <<<"$resp" >/dev/null 2>&1; then
+    log "api call failed, raw response: ${resp:0:300}"
+    echo ""
+    return
+  fi
+  jq -r '.choices[0].message.content' <<<"$resp"
 }
 
 repo_context() { git ls-files | head -120; }