* feat(providers): remove google-gemini-cli + google-antigravity OAuth providers
Google now actively bans accounts for third-party tools that piggyback on
Gemini CLI / Antigravity / Code Assist OAuth, and because abuse prevention
sits at a backend layer the ban can extend to the entire Google account
(Gmail/Drive), with a second violation being permanent.
Ref: https://github.com/google-gemini/gemini-cli/discussions/20632
Removes both OAuth inference providers entirely (modules, provider profiles,
auth/runtime/config/models wiring, the /gquota Code Assist quota command,
the antigravity-cli optional skill, desktop + docs surface in en + zh-Hans).
The API-key 'gemini' provider (GOOGLE_API_KEY/GEMINI_API_KEY against
generativelanguage.googleapis.com) is unaffected and stays fully supported.
* fix(skills): keep the antigravity-cli skill — only the OAuth provider is removed
The antigravity-cli optional skill orchestrates the external `agy` binary as
a coding-agent tool via the terminal tool — it does NOT wrap Hermes inference
through the banned google-antigravity OAuth provider, so it carries none of
the account-ban risk that motivated removing that provider. Restore the skill,
its docs page, the sidebar entry, and the optional-skills catalog row. The
google-antigravity / google-gemini-cli inference providers stay fully removed.
Adds hermes_cli/provider_catalog.py, deriving one descriptor per provider from
the CANONICAL_PROVIDERS universe (what `hermes model` renders, auto-extended
from provider plugins), joined with auth/env from PROVIDER_REGISTRY and display
metadata from ProviderProfile (with canonical/env fallbacks for the four
profile-less providers and the many profiles with blank display/signup fields).
Each descriptor is tagged with the desktop tab it belongs on (keys vs accounts)
by auth_type. This is the single source of truth the desktop Providers tabs will
derive membership from, so they can no longer drift from the CLI picker.
Tests assert the parity contract (catalog == hermes model universe) and tab
routing as invariants, not snapshots.
