init: seed framework reference content from agent-runtimes main repo

harnesses/capabilities/tdd-file-lock/v1/harness.yaml

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+kind: capability
+name: tdd-file-lock
+version: 1
+description: "Locks /workspace/tests/ read-only (root-owned). Agent cannot modify test files."
+requires: []
+
+scripts:
+  init: "./init.sh"

harnesses/capabilities/tdd-file-lock/v1/init.sh

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+#!/bin/bash
+# TDD file lock — runs as root before agent user takes over.
+# Creates a root-owned immutable reference copy of tests/ and locks the
+# working copy so the agent cannot write to any test file.
+set -euo pipefail
+
+if [ ! -d "/workspace/tests" ]; then
+    echo "[tdd-file-lock] No /workspace/tests found — nothing to protect."
+    exit 0
+fi
+
+echo "[tdd-file-lock] Locking test files (running as $(id))..."
+
+# Root-owned reference copy — agent cannot chmod/write/delete these
+mkdir -p /workspace/reference/tests
+cp -r /workspace/tests/. /workspace/reference/tests/
+chown -R root:root /workspace/reference/tests
+find /workspace/reference/tests -type f -exec chmod 444 {} \;
+find /workspace/reference/tests -type d -exec chmod 555 {} \;
+
+# SHA256 checksums for post-task external verification
+find /workspace/tests -name "*.py" | sort | xargs sha256sum > /workspace/.test-shas
+chown root:root /workspace/.test-shas
+chmod 444 /workspace/.test-shas
+
+# Lock the working tests/ directory — files and dirs owned by root, no write for anyone
+chown -R root:root /workspace/tests
+find /workspace/tests -type f -exec chmod 444 {} \;
+find /workspace/tests -type d -exec chmod 555 {} \;
+
+TEST_COUNT=$(find /workspace/tests -name "*.py" | wc -l)
+echo "[tdd-file-lock] Protected ${TEST_COUNT} test files."
+echo "[tdd-file-lock] Immutable reference: /workspace/reference/tests/"
+echo "[tdd-file-lock] SHA256 reference:    /workspace/.test-shas"