Keep Homebrew's baseline read_write path in permissive OpenClaw policies so live policy transitions used by shields down and network-policy E2E do not attempt to remove /home/linuxbrew after #3916. Adds regression coverage that permissive policies retain baseline read_write paths.

Rewrites the two passive sentences flagged by review in the new
Homebrew Specifics subsection and the brew preset row of the
security best-practices table, and regenerates the matching agent
skill mirrors. No content change beyond voice; the post-NVIDIA#3916
flow (apply preset, then brew install) is unchanged.

Signed-off-by: latenighthackathon <support@latenighthackathon.com>
Signed-off-by: latenighthackathon <latenighthackathon@users.noreply.github.com>

After NVIDIA#3916 baked Homebrew (Linuxbrew) into the sandbox base image,
the brew preset is the only step needed before installing a formula.
Update the integration policy examples, the security best-practices
preset table, and the brew preset description to reflect the new
flow so users no longer expect a separate Homebrew bootstrap.

Signed-off-by: latenighthackathon <latenighthackathon@users.noreply.github.com>

Rewrites the two passive sentences flagged by review in the new
Homebrew Specifics subsection and the brew preset row of the
security best-practices table, and regenerates the matching agent
skill mirrors. No content change beyond voice; the post-NVIDIA#3916
flow (apply preset, then brew install) is unchanged.

Signed-off-by: latenighthackathon <latenighthackathon@users.noreply.github.com>

…3946)

## Summary

Updates the network-policy docs and the brew preset description so users
know that the brew binary already ships in the sandbox base image after
#3916, and the brew preset is the only step needed before installing a
formula.

## Problem

Before #3916 landed, the brew preset only granted network egress and
assumed Homebrew was already on PATH. Several pages still describe brew
as a generic package-manager preset without mentioning that the binary
is now baked into the image, so a new user following the integration
policy examples can be left looking for a separate bootstrap step that
no longer applies. This PR brings those pages and the preset description
in line with the post-#3916 flow.

## Changes

- docs/network-policy/integration-policy-examples.mdx: add a short
"Homebrew Specifics" subsection under Package and Model Tooling that
explains the post-#3916 flow with a concrete policy-add brew + exec --
brew install example, and notes that no separate Homebrew bootstrap,
build dependency install, or `brew shellenv` step is required.
- docs/security/best-practices.mdx: expand the brew preset row in the
policy preset table to note that the binary is preinstalled and the
preset only opens network egress to GitHub and the Homebrew formulae
index.
- nemoclaw-blueprint/policies/presets/brew.yaml: clarify in the preset
description and a YAML comment that the brew binary is preinstalled
(referencing #3913).
-
.agents/skills/nemoclaw-user-{configure-security,manage-policy}/references/*.md:
regenerated via the canonical docs-to-skills invocation so the agent
skill mirrors stay in sync with the source pages.

## Test plan

- python3 scripts/docs-to-skills.py docs/ .agents/skills/ --prefix
nemoclaw-user --doc-platform fern-mdx: skill regen runs to completion
and only touches the two expected reference mirrors.
- Pre-commit + pre-push hooks (markdownlint-cli2, Verify docs-to-skills
output, Test (skills YAML), Source-shape test budget, TypeScript (CLI),
gitleaks, NEMOCLAW_* env-var doc gate, etc.) all pass on the docs-only
diff.

Signed-off-by: latenighthackathon
<latenighthackathon@users.noreply.github.com>


<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **Documentation**
* Expanded security best-practices entry for the Homebrew preset to
explain what the preset enables and the risk of installing arbitrary
packages.
* Added a “Homebrew Specifics” integration guide with usage examples
showing how to apply the preset and run brew installs in the sandbox.
* Clarified that Homebrew is preinstalled in the sandbox base image and
that the preset grants outbound access to fetch formulae/bottles.

<!-- review_stack_entry_start -->

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<!-- end of auto-generated comment: release notes by coderabbit.ai -->

---------

Signed-off-by: latenighthackathon <latenighthackathon@users.noreply.github.com>
Co-authored-by: latenighthackathon <latenighthackathon@users.noreply.github.com>

## Summary

Fixes #3757 as a follow-up to #3916. The base image now exposes `brew`
on the normal sandbox `PATH` without making Homebrew infer `/usr/local`
as its prefix.

## Problem

#3916 correctly baked Homebrew into `/home/linuxbrew/.linuxbrew`, but it
exposed the entry point with a plain `/usr/local/bin/brew` symlink. In a
fresh sandbox that made Homebrew report `/usr/local` as the prefix,
which broke the QA path in two ways:

- `brew install --quiet hello` tried to create locks under root-owned
`/usr/local/var/homebrew`.
- On arm64, Homebrew rejected the Intel/default `/usr/local` prefix.

After fixing the prefix, installed formula commands also need to be
reachable in sandbox shell sessions without asking users to source `brew
shellenv` manually.

## Changes

- Replace the `/usr/local/bin/brew` symlink with a wrapper that execs
`/home/linuxbrew/.linuxbrew/bin/brew`, preserving the Linuxbrew prefix.
- Add build-time assertions that `/usr/local/bin/brew --prefix` and
sandbox login-shell `brew --prefix` both return
`/home/linuxbrew/.linuxbrew`.
- Add `/home/linuxbrew/.linuxbrew/bin` through
`/etc/profile.d/nemoclaw-linuxbrew.sh` only for the `sandbox` user,
while deliberately avoiding a global Docker `ENV PATH` entry for the
sandbox-writable Linuxbrew prefix.
- Add network-policy E2E coverage for the real QA path: apply `brew`,
install `hello`, resolve `hello` on PATH, and run it.
- Update the Homebrew docs wording from symlink to wrapper and show
shell-session execution for installed formula commands.

## Validation

- `npm run build:cli`
- `npm run typecheck:cli`
- `npx vitest run test/policies.test.ts`
- `npm run source-shape:check`
- `hadolint Dockerfile.base`
- `bash -n test/e2e/test-network-policy.sh`
- `shellcheck test/e2e/test-network-policy.sh`
- `git diff --check`
- Throwaway base-image behavior smoke with this wrapper/profile change
applied in-container and no global Linuxbrew `PATH`:
  - root login shell does not include `/home/linuxbrew/.linuxbrew/bin`
- direct `/usr/local/bin/brew --prefix` -> `/home/linuxbrew/.linuxbrew`
  - sandbox login shell includes `/home/linuxbrew/.linuxbrew/bin`
  - `brew install --quiet hello` succeeds
  - `command -v hello` -> `/home/linuxbrew/.linuxbrew/bin/hello`
  - `hello` -> `Hello, world!`

## Local caveats

- Full `docker build -f Dockerfile.base ...` could not run on this host
because Docker has no working buildx/BuildKit component; the legacy
builder fails on the existing `RUN --mount` step before reaching this
change.
- `npx vitest run test/nemoclaw-start.test.ts test/policies.test.ts`
passed the related policy coverage but still hit existing local fixture
failures in `test/nemoclaw-start.test.ts` because
`nemoclaw/node_modules/json5` is absent in this worktree.
`test/policies.test.ts` passes by itself.
- `npx prek run --files Dockerfile.base
docs/network-policy/integration-policy-examples.mdx
test/policies.test.ts` passed the visible file hooks including hadolint,
gitleaks, docs-to-skills, and source-shape, then failed in the full CLI
test hook on the same unrelated `test/nemoclaw-start.test.ts`
baseline-capture failures plus a coverage temp-file ENOENT.


<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **Chores**
* Switched Homebrew runtime to a wrapper-script approach and
conditionally expose the package manager bin on sandbox shell PATH
* Added runtime validations to ensure wrapper and PATH behave correctly
across privileged and sandbox sessions
  * Made sandbox command execution timeouts configurable

* **Documentation**
* Clarified wrapper behavior and how installed commands are available in
sandbox sessions

* **Tests**
  * Updated test wording to reference "PATH wrapper"
* Added an end-to-end test validating install/use flow and expected
runtime behavior (TC-NET-11)

<!-- review_stack_entry_start -->

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---------

Signed-off-by: Aaron Erickson <aerickson@nvidia.com>