feat: restore CI/release, prompt contracts, faster install (0.9.33)

Bring back Gitea CI + auto-publish; share release helpers; strengthen multi-turn
tool/job prompts with a unit contract; ccache/make help and --release bootstrap.

Co-authored-by: Cursor <cursoragent@cursor.com>

scripts/prompt_smoke.sh

@@ -0,0 +1,10 @@
+#!/usr/bin/env bash
+# Offline multi-round prompt smoke: builds the agent and runs the prompt
+# contract unit test (no API key). Used by local loops and CI-adjacent checks.
+set -euo pipefail
+ROOT="$(cd "$(dirname "$0")/.." && pwd)"
+cd "$ROOT"
+jobs="$(nproc 2>/dev/null || echo 4)"
+make -j"$jobs" tests/test_prompt_contract cst-agent
+./tests/test_prompt_contract
+echo "prompt_smoke: OK"