1c75e7c9d8
The Keys page only rendered env vars present in a catalog (OPTIONAL_ENV_VARS or the provider catalog); any other key a user set in .env was invisible, and there was no way to add an arbitrary env var from the GUI (e.g. to inject a var a skill or MCP server needs). Backend: GET /api/env now also emits a row for every on-disk .env key that isn't in any catalog, flagged category="custom" + custom=true and password-masked (an unrecognised key could hold anything, so it's redacted and reveal-gated like any secret). Channel-managed credentials stay excluded. The write (PUT /api/env) and reveal (POST /api/env/reveal) paths already handle arbitrary keys, with the existing env-name guard + denylist (PATH, LD_PRELOAD, PYTHONPATH, …) enforced server-side — no new write surface. Frontend: a new "Custom Keys" section lists those custom rows and carries an add-a-key form (client-side name validation mirroring the backend regex; the new row reuses the normal edit/save flow, so on save it round-trips back from the backend as a durable custom row). i18n added for en + zh + types. Tests: behavior-contract coverage that an unknown .env key surfaces as a masked custom row and a catalogued key does not — verified to fail on the pre-fix backend.