fix: sink nodes should be Component not Output unless named output/result/end

Previously, the last node in any triplet chain was classified as Output type
and skipped by the executor (passthrough only). Now only nodes explicitly named
output/result/end/done are Output; all other sink nodes are Component and
will have their WASM executed.

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

cypher-executor/src/actions/triplet-parser.ts

@@ -101,10 +101,23 @@ export function parseTriplets(rawTriplets: unknown[]): ParsedTriplets | null {
   return { edges, nodeNames, sourceNodes, sinkNodes };
 }
 
-/** 根據節點在圖中的位置決定其 type */
+/** 保留字節點名稱 — 明確宣告為 Input 或 Output 端點 */
+const INPUT_NAMES = new Set(['input', 'trigger', 'webhook', 'start']);
+const OUTPUT_NAMES = new Set(['output', 'result', 'end', 'done']);
+
+/** 根據節點在圖中的位置決定其 type
+ *
+ *  規則：
+ *  - 名稱在 INPUT_NAMES  → Input（無論位置）
+ *  - 名稱在 OUTPUT_NAMES → Output（無論位置）
+ *  - sourceNode（只出現在 from）且名稱不在 INPUT_NAMES → Component（例如 cron 作為觸發源）
+ *  - sinkNode（只出現在 to）且名稱不在 OUTPUT_NAMES → Component（最常見情況：最後一個實際零件）
+ *  - 其他中間節點 → Component
+ */
 export function resolveNodeRole(name: string, parsed: ParsedTriplets): NodeRole {
+  if (INPUT_NAMES.has(name.toLowerCase())) return 'Input';
+  if (OUTPUT_NAMES.has(name.toLowerCase())) return 'Output';
   if (parsed.sourceNodes.has(name)) return 'Input';
-  if (parsed.sinkNodes.has(name)) return 'Output';
   return 'Component';
 }