A repository per test run instead of the shared sandbox

Every live test that touches a repository gets one of its own from
e2e_support.fresh_repo, made by the test operator as an operator makes a
project's (D4, D8): seeded from tests/integration/seed/ (the sandbox's
package, without past runs' leftovers), the agent's account a collaborator
with write access, main protected (pushes only by the owner, an approval to
merge), and a deploy key generated for the run. It is deleted afterwards
(NISSE_E2E_KEEP_REPOS keeps it); scripts/e2e-cleanup.sh deletes leftovers.

- Both e2e fixtures use it; per-run base branches are gone. The merge
  helper approves first, as the protection now requires.
- test_gitea_live uses it, so CI needs NISSE_OPERATOR_TOKEN and no longer
  writes the sandbox deploy key (NISSE_PUSH_KEY).
- A live test of the helper: seeded, shared with the agent, protected
  against it, deleted.
- nisse-test.yaml's project entry is a placeholder; pytest and ruff skip
  the seed.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PPQ14L3LikyefCMFBqEbKE

tests/integration/seed/tests/test_factorial.py

@@ -0,0 +1,42 @@
+import math
+
+import pytest
+
+from sandbox import factorial
+
+
+@pytest.mark.parametrize(
+    "n, expected",
+    [
+        (0, 1),
+        (1, 1),
+        (2, 2),
+        (3, 6),
+        (5, 120),
+        (10, 3628800),
+        (20, 2432902008176640000),
+    ],
+)
+def test_factorial_known_values(n, expected):
+    assert factorial(n) == expected
+
+
+def test_factorial_matches_math_factorial():
+    for n in range(0, 101):
+        assert factorial(n) == math.factorial(n)
+
+
+def test_factorial_large_input_no_recursion_limit():
+    assert factorial(2000) == math.factorial(2000)
+
+
+@pytest.mark.parametrize("n", [-1, -5, -100])
+def test_factorial_negative_raises_value_error(n):
+    with pytest.raises(ValueError):
+        factorial(n)
+
+
+@pytest.mark.parametrize("n", [5.0, 2.5, "5", None, True, False])
+def test_factorial_non_int_raises_type_error(n):
+    with pytest.raises(TypeError):
+        factorial(n)

tests/integration/seed/tests/test_slugify.py

@@ -0,0 +1,25 @@
+import pytest
+
+from sandbox.slugify import slugify
+
+
+@pytest.mark.parametrize(
+    "text, expected",
+    [
+        ("Hello World", "hello-world"),
+        ("Hello, World!", "hello-world"),
+        ("  leading and trailing  ", "leading-and-trailing"),
+        ("multiple   spaces", "multiple-spaces"),
+        ("a--b__c..d", "a-b-c-d"),
+        ("!!!", ""),
+        ("", ""),
+        ("-already-slugged-", "already-slugged"),
+        ("MiXeD CaSe 123", "mixed-case-123"),
+        ("tab\tand\nnewline", "tab-and-newline"),
+        ("Café Déjà Vu", "cafe-deja-vu"),
+        ("emoji 🎉 party", "emoji-party"),
+        ("Foo Bar", "foo-bar"),
+    ],
+)
+def test_slugify(text, expected):
+    assert slugify(text) == expected

tests/integration/seed/tests/test_truncate.py

@@ -0,0 +1,37 @@
+import pytest
+
+from sandbox import truncate
+
+
+@pytest.mark.parametrize(
+    "text, n, expected",
+    [
+        ("", 1, ""),
+        ("abc", 3, "abc"),
+        ("abc", 10, "abc"),
+        ("abcd", 3, "ab\u2026"),
+        ("hello world", 5, "hell\u2026"),
+        ("ab", 1, "\u2026"),
+        ("a", 1, "a"),
+        ("h\u00e9llo w\u00f6rld", 4, "h\u00e9l\u2026"),
+    ],
+)
+def test_truncate_cases(text, n, expected):
+    assert truncate(text, n) == expected
+
+
+@pytest.mark.parametrize("n", range(1, 16))
+def test_result_never_exceeds_n(n):
+    assert len(truncate("hello world!!", n)) <= n
+
+
+def test_uses_single_ellipsis_char():
+    result = truncate("hello world", 5)
+    assert result.endswith("\u2026")
+    assert not result.endswith("...")
+
+
+@pytest.mark.parametrize("n", [0, -5])
+def test_invalid_n_raises(n):
+    with pytest.raises(ValueError):
+        truncate("abc", n)