(chore) add associate tasks

tasks/4.4-api-exec.md

@@ -0,0 +1,14 @@
+# 4.4 — POST /api/exec (GREEN)
+
+Phase: 4 — Terminal (Surface C)
+Stage: GREEN
+
+Depends on: [4.1](4.1-exec-parse-test.md), [4.2](4.2-exec-test.md)
+
+- [ ] `POST /api/exec` — session cookie, 20/min/session; input parses to a closed command enum, anything unmatched rejected before any lookup
+
+## Verify
+
+```bash
+curl -X POST https://riotpiao.com/api/exec -d '{"cmd":"get pods; rm -rf /"}'
+```