v1.91.159.0 security: gstack's Bun entry points ignore the audited repo's .env and bunfig.toml (S1) (#3312)

* security: isolate every gstack Bun entry point from the audited checkout's .env and bunfig.toml

Bun auto-loads .env, .env.local and .env.<NODE_ENV> from its cwd and runs a
cwd bunfig.toml preload before the program starts. gstack runs inside the repo
it audits, so a committed .env could steer state roots, the claude binary or
spend caps, and a bunfig preload ran arbitrary code in every bin and hook.

Every bun shebang, shell and skill caller, TypeScript spawn and compiled build
now disables both (--no-env-file --config=/dev/null, bunIsolationArgs(),
--no-compile-autoload-dotenv/bunfig), with a ratchet and hostile-fixture
regressions.

Co-authored-by: capy-ai[bot] <230910855+capy-ai[bot]@users.noreply.github.com>

* test: name the directly executed scripts in the isolation ratchet

Co-authored-by: capy-ai[bot] <230910855+capy-ai[bot]@users.noreply.github.com>

* test: follow the isolation flags in touchfiles, copy lists, recipe assertions and the harness pin

Co-authored-by: capy-ai[bot] <230910855+capy-ai[bot]@users.noreply.github.com>

* fix: keep browse/src/bun-child-config.ts unchanged so the native cookie qualification still binds

Co-authored-by: capy-ai[bot] <230910855+capy-ai[bot]@users.noreply.github.com>

* fix(windows): the empty bunfig outlives its process so the timeline hook's detached repair child can read it

Co-authored-by: capy-ai[bot] <230910855+capy-ai[bot]@users.noreply.github.com>

* v1.91.159.0 security: gstack's Bun entry points ignore the audited repo's .env and bunfig.toml (S1)

Co-authored-by: capy-ai[bot] <230910855+capy-ai[bot]@users.noreply.github.com>

* test: plan-mode render pattern accepts the isolation flags

Co-authored-by: capy-ai[bot] <230910855+capy-ai[bot]@users.noreply.github.com>

---------

Co-authored-by: capy-ai[bot] <230910855+capy-ai[bot]@users.noreply.github.com>

bin/gstack-brain-cache

@@ -1,4 +1,4 @@
-#!/usr/bin/env bun
+#!/usr/bin/env -S bun --no-env-file --config=/dev/null
 /**
  * gstack-brain-cache — three-tier cache for brain-aware planning skills.
  *