Every credential source Hermes reads from now behaves identically on
`hermes auth remove`: the pool entry stays gone across fresh load_pool()
calls, even when the underlying external state (env var, OAuth file,
auth.json block, config entry) is still present.
Before this, auth_remove_command was a 110-line if/elif with five
special cases, and three more sources (qwen-cli, copilot, custom
config) had no removal handler at all — their pool entries silently
resurrected on the next invocation. Even the handled cases diverged:
codex suppressed, anthropic deleted-without-suppressing, nous cleared
without suppressing. Each new provider added a new gap.
What's new:
agent/credential_sources.py — RemovalStep registry, one entry per
source (env, claude_code, hermes_pkce, nous device_code, codex
device_code, qwen-cli, copilot gh_cli + env vars, custom config).
auth_remove_command dispatches uniformly via find_removal_step().
Changes elsewhere:
agent/credential_pool.py — every upsert in _seed_from_env,
_seed_from_singletons, and _seed_custom_pool now gates on
is_source_suppressed(provider, source) via a shared helper.
hermes_cli/auth_commands.py — auth_remove_command reduced to 25
lines of dispatch; auth_add_command now clears ALL suppressions for
the provider on re-add (was env:* only).
Copilot is special: the same token is seeded twice (gh_cli via
_seed_from_singletons + env:<VAR> via _seed_from_env), so removing one
entry without suppressing the other variants lets the duplicate
resurrect. The copilot RemovalStep suppresses gh_cli + all three env
variants (COPILOT_GITHUB_TOKEN, GH_TOKEN, GITHUB_TOKEN) at once.
Tests: 11 new unit tests + 4059 existing pass. 12 E2E scenarios cover
every source in isolated HERMES_HOME with simulated fresh processes.
