On Windows, show PowerShell syntax ($env:NODE_EXTRA_CA_CERTS=...),
on Unix show export syntax.

All platform detection must go through src/helpers/platform.ts.
Direct process.platform access outside platform.ts is forbidden.

Also fixes flaky Windows test failures:
- Replace Bun.$ with Bun.spawn in git test helpers (ARCH-007)
- Add safeRmSync with retries for Windows EBUSY errors
- Increase timeouts for git-commit-heavy tests

When token claim fails because the user is not registered, the login
command now prompts for email and use case, submits a signup request
to the plugins API, and immediately retries the token claim (since
signups are auto-approved).

getGitHubUser now returns both login and email from the GitHub API.
The signup prompt pre-fills the email field when available.

- requestSignup now returns the token from the API response, avoiding
  a second token claim round-trip and duplicate tokens in the database
- Signup flow prompts for editor preference (Claude Code / Cursor)
- Falls back to claimArchgateToken if the signup response has no token

Match the frontend's editor choices: Claude Code, VS Code, Copilot CLI,
and Cursor.

If .archgate/adrs/ exists in the current project, suggest running
`archgate check` instead of `archgate init`.

- Login section now documents automatic signup flow for unregistered users
- Added troubleshooting section for TLS/corporate proxy errors
- Updated example output to show signup prompts and context-aware hints
- Updated beta tips to reflect CLI-based signup (no external site needed)
- All changes mirrored in PT-BR documentation

When running `archgate init` without credentials, the CLI now asks
if the user wants to install the editor plugin. If yes, it runs the
full GitHub device flow + signup inline, then continues with plugin
installation.

Skips interactive prompts in non-TTY environments (agent-driven runs)
to avoid blocking MCP servers and onboarding agents.

The device flow, signup prompt, and credential storage logic was
duplicated between login.ts and init.ts. Now both commands use
runLoginFlow() from helpers/login-flow.ts.

When the editor is already known (init --editor), the signup prompt
skips the editor question.

Write docs as if the reader is seeing them for the first time,
not announcing what changed.

The editor plugin section on both EN and PT-BR index pages now
links to all four editor integration guides.
Also fixes PT-BR index links to use /pt-br/ prefix.

Starlight resolves locale routes automatically, so PT-BR pages should
use /guides/... not /pt-br/guides/.... The new no-locale-prefix-in-links
rule catches this. Also fixes 28 pre-existing violations across PT-BR docs.

Regenerates llms-full.txt during CI and fails if there's a diff,
ensuring it stays in sync with documentation changes.

Adds a workflow that regenerates and auto-commits llms-full.txt
when docs content changes in a PR, matching the update-lock pattern.
Removes the manual check from the validation workflow.

The auto-commit workflow handles PRs, but the check catches
direct pushes or workflow failures.