feat(security): dedicated install flags decoupled from security_level (#2991)

* feat(security): add dedicated install flags decoupled from security_level

Gate 'install via git URL' and 'install via pip' with dedicated opt-in
boolean flags (allow_git_url_install / allow_pip_install) in config.ini
[default], fully replacing the security_level term on those surfaces
(REPLACE, not AND — a strict level no longer denies when the flag is on;
a weak level no longer allows when the flag is off).

- glob/manager_server.py: pure predicate is_dedicated_install_allowed
  (flag AND loopback, request-time args.listen); REPLACE gates at
  /customnode/install/git_url and /customnode/install/pip; batch
  unknown-URL arm routes through the same full predicate at the risky
  position (loopback term is load-bearing — the middle entry gate has
  no network-position term; the entry gate itself stays in force);
  unknown-pip in batch stays unconditionally blocked; new
  SECURITY_MESSAGE_FLAG_* denial constants name the responsible flag;
  security_403_response gains flag_token (comfyui_outdated keeps precedence)
- glob/manager_core.py: register both keys (read via get_bool default-false,
  write list, exception fallback); "true"-only truthy; restart-only activation
- js/common.js: 403 dialog copy names the responsible flag at the two
  install call sites
- README.md: security-policy docs for both flags (per-surface scope incl.
  the batch entry-gate qualifier, REPLACE decoupling, loopback bound,
  opt-in config snippet, default-deny + migration note); stale tier lists
  corrected against the actual gates
- CHANGELOG.md: opt-in migration note + accepted residual risk (flags
  bypass the forced-strong outdated-ComfyUI hardening on loopback,
  opt-in only), decoupling claim qualified for the batch entry gate

Tests: unit suite (predicate truth table, REPLACE litmus both directions,
AST binding-proofs against live handlers, subprocess-isolated config
contract) plus a real-server E2E suite that mounts the Manager-under-test
via git worktree (exact-SHA pin, detached) against a real ComfyUI and
exercises both flag surfaces and both arms — deny arms (403 + flag-naming
body/log + no install artifact), git-URL allow arm (real clone), pip allow
arm as a two-phase reservation oracle — with zero-residual self-clean.
Module skips without E2E_COMFYUI_ROOT; unit suite unaffected.

The manager-v4 branch ships the identical policy (shared invariants +
config contract); this tree uses the degraded predicate 'flag AND
loopback' (no personal_cloud-equivalent mode here).

* bump version to v3.41

tests/conftest.py

@@ -0,0 +1,41 @@
+"""Test-runner guard for the GOAL #32 tests/ modules.
+
+WHY THIS FILE EXISTS (collection hazard, not test logic):
+
+The repo root contains ``__init__.py`` — the ComfyUI plugin entrypoint —
+which at import time appends ``glob/`` to sys.path and imports
+``manager_server`` (which needs ``folder_paths`` / ``comfy.cli_args`` /
+a constructed ``PromptServer``). pytest 8 collects any ancestor
+directory that carries an ``__init__.py`` as a ``Package`` node and
+IMPORTS that ``__init__.py`` during test setup (observed module name:
+``__init__``). Outside a live ComfyUI process that import can never
+succeed, so EVERY test under tests/ errors at setup — including the
+pre-existing tests/test_csrf_content_type_helper.py — whenever pytest's
+rootdir ends up at or above the repo root (e.g. running inside a git
+worktree nested under the parent checkout).
+
+The guard below pre-seeds ``sys.modules`` with an inert stub whose
+``__file__`` matches the real path, so pytest's
+``import_path(<repo-root>/__init__.py)`` resolves to the stub without
+executing the plugin entrypoint. Conftest files load before the setup
+phase, so the stub is always in place in time. This does NOT touch
+production code and does NOT alter what the tests import themselves
+(they use AST-extraction / subprocess isolation per the
+tests/test_csrf_content_type_helper.py precedent — ``glob/`` is never
+added to the runner's sys.path).
+"""
+import sys
+import types
+from pathlib import Path
+
+_REPO_ROOT = Path(__file__).resolve().parent.parent
+_ROOT_INIT = _REPO_ROOT / "__init__.py"
+
+if _ROOT_INIT.exists() and "__init__" not in sys.modules:
+    _stub = types.ModuleType("__init__")
+    _stub.__file__ = str(_ROOT_INIT)
+    _stub.__doc__ = (
+        "Inert stand-in for the ComfyUI-Manager plugin entrypoint; "
+        "see tests/conftest.py for rationale."
+    )
+    sys.modules["__init__"] = _stub