Implement the four Gemini native inbound endpoints so Gemini CLI / Google
GenAI SDKs can point their base URL at the gateway:
- GET /v1beta/models — directory listing in Gemini shape, built from
configured routes (like /v1/models); no upstream call, no billing.
- POST /v1beta/models/{model}:generateContent — non-streaming, routed
through ProxyConductor with failover + usage_logs + billing.
- POST /v1beta/models/{model}:streamGenerateContent — SSE passthrough via
open_stream_with_failover + sse_passthrough_response.
- POST /v1beta/models/{model}:countTokens — metadata call, routed for a
channel but not billed.
Auth accepts the gateway key from ?key= or x-goog-api-key (Gemini
convention) and reuses the downstream-key authorization + limits.
Billing closes the loop: gemini_extract_usage reads usageMetadata
(promptTokenCount / candidatesTokenCount) for non-streaming, and
gemini_stream_usage_from_line feeds the shared StreamUsageAccumulator so
streamed usageMetadata is billed too.
Unit tests cover model:action parsing, usage extraction, the stream usage
parser, and query forwarding (key/alt dropped).
Previously every executor took `_state: AppState` (unused) and `check_auth`
discarded the matched downstream key id, so `usage_logs` was orphan code.
This change plumbs the key id from auth → handlers → executors → billing,
adds the OpenAI Responses API endpoint, and exposes shim aliases under
`/api/comfyui-agent/proxy/openai/*` so embedded ComfyUI's OpenAI nodes
flow through the same auth/conductor/billing pipeline.
- check_auth now returns Option<i64> (managed key id) instead of unit
- record_billing helper writes usage_logs after each successful upstream call
- extract_usage handles both chat-completions and responses usage shapes
- conductor wrappers record billing post-Success; stream variant scans
chunks in reverse for the final usage event
- POST /v1/responses (stream + non-stream) via ProxyConductor
- shim aliases mounted on the same Router so auth/failover/billing work for free
- ComfyUIProcess injects BOOSAPI_BUILTIN_KEY env + --comfy-api-base on spawn
- bootstrap built-in `comfyui-agent` downstream key at startup (idempotent)
- get_auth_header in vendored ComfyUI falls back to BOOSAPI_BUILTIN_KEY env
Co-Authored-By: Kiro <noreply@kiro.dev>
boos