governance: keep repository root clean; remove marker file; implement repo detection via structure heuristic; update tests and system prompts/templates

tests/helpers/assert.sh

@@ -0,0 +1,24 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+fail() { echo "ASSERTION FAILED: $*" >&2; return 1; }
+
+assert_eq() {
+  local expected="$1" actual="$2"; shift 2
+  if [ "$expected" != "$actual" ]; then
+    fail "expected='$expected' actual='$actual' $*"
+  fi
+}
+
+assert_contains() {
+  local haystack="$1" needle="$2"; shift 2
+  if ! grep -Fq -- "$needle" <<<"$haystack"; then
+    fail "did not find '$needle' in output"
+  fi
+}
+
+run_cmd() {
+  local out err rc
+  out="$({ err=$( { "$@"; } 2>&1 1>&3 ); rc=$?; echo "$err" >&2; echo $rc >&4; } 3>&1 4>&1)"
+}
+