www/code-server: Update to 4.129.0

Update to code-server 4.129.0, which bundles VS Code 1.129.0.

VS Code 1.129 changed how the built-in GitHub Copilot extension is
handled: it is now built from source during the reh-web build instead
of being fetched as a prebuilt VSIX. This requires a few build-time
workarounds:

• The copilot extension postinstall expects a platform package for the host. A Copilot CLI SDK distfile is provided and placed as @github/copilot-freebsd-x64 so the postinstall passes. GitHub Copilot is closed-source and not usable on FreeBSD; this only lets the build complete.
• The reh-web build calls ensureCopilotPlatformPackage(), which runs "npm pack" and thus needs network access (unavailable in poudriere). Providing @github/copilot-linux-x64 in remote/node_modules makes the function find it locally and skip the network fetch.
• Copilot bundles prebuilt Linux rg/tgrep binaries. These are replaced with native FreeBSD binaries from textproc/ripgrep and textproc/tgrep so that no Linux ELF binaries ship in the package.

Additional changes:

• Add ONLY_FOR_ARCHS=amd64; only a linux-x64 vscode-reh-web distfile is provided.
• Drop test/* entries from VSCODE_NODE_MODULES; test suites do not belong in the server package.
• Add a code_server_shell rc variable (default /bin/sh) so the built-in terminal works when the service runs as nobody, whose login shell is /usr/sbin/nologin.
• Fix ${PREFIX} expansion in pkg-message.

Sponsored by: Netzkommune GmbH