[Bubblewrap] Scrub inherited FTP proxy env variables

[Soham Das (SohamDas2021)]

📖 Description

Adds FTP_PROXY and ftp_proxy to the managed proxy-variable set so caller-supplied FTP proxy settings cannot conflict with an MXC-configured proxy. Extends shared and Bubblewrap unit tests.

🔗 References

Refs AB#62864253.

🔍 Validation

✅ Checklist

• Signed the Contributor License Agreement
• Linked to an issue
• Updated documentation (if applicable)
• Updated Copilot instructions (if build, architecture, or conventions changed)
• If this PR changes Cargo.lock, the dependency-feed-check check passes (see docs/pull-requests.md)

📋 Issue Type

• Bug fix
• Feature
• Task

---

GitHub Actions runs the PR validation build automatically. The ADO pipeline
(MXC-PR-Build) is the Azure version of the PR pipeline, kept in parity with the GitHub
Actions build; it runs on merge to main, and Microsoft reviewers with write access can trigger it
on a PR with /azp run. See docs/pull-requests.md.

If the dependency-feed-check check fails on a new dependency, the crate must be added to
the feed before the PR can pass. See docs/pull-requests.md
for the steps.

Microsoft Reviewers: Open in CodeFlow

[azure-pipelines]

Azure Pipelines:
There may be pipelines that require an authorized user to comment /azp run to run.

[Copilot]

Pull request overview

Adds FTP proxy variables to MXC’s managed proxy environment set and extends regression tests.

Changes:

• Scrubs uppercase and lowercase FTP proxy variables.
• Tests shared and Bubblewrap proxy handling.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
src/core/wxc_common/src/proxy_env.rs	Adds FTP variables to managed proxy keys.
src/backends/bubblewrap/common/src/bwrap_command.rs	Tests FTP variable scrubbing.

---

💡 Add a code-review agent skill or configure MCP servers for context-aware, tailored reviews. Learn more in the docs.

[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.