feat(gateway): dual-mount legacy routers on /api and /api/v1 (Stage 1 PR5)

Strip /api prefix from 13 legacy router APIRouter() declarations and dual-mount
each on prefix="/api" (backward compat) and prefix="/api/v1" (versioned surface)
in app.py. Auth, service-accounts, api-keys, assistants-compat remain single-mount.
Update 10 test files to pass prefix="/api" when directly including stripped routers.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

backend/app/gateway/routers/agents.py

@@ -14,7 +14,7 @@ from deerflow.config.paths import get_paths
 from deerflow.runtime.user_context import get_effective_user_id
 
 logger = logging.getLogger(__name__)
-router = APIRouter(prefix="/api", tags=["agents"])
+router = APIRouter(tags=["agents"])
 
 AGENT_NAME_PATTERN = re.compile(r"^[A-Za-z0-9-]+$")
 

backend/app/gateway/routers/artifacts.py

@@ -12,7 +12,7 @@ from app.gateway.path_utils import resolve_thread_virtual_path
 
 logger = logging.getLogger(__name__)
 
-router = APIRouter(prefix="/api", tags=["artifacts"])
+router = APIRouter(tags=["artifacts"])
 
 ACTIVE_CONTENT_MIME_TYPES = {
     "text/html",

backend/app/gateway/routers/channels.py

@@ -9,7 +9,7 @@ from pydantic import BaseModel
 
 logger = logging.getLogger(__name__)
 
-router = APIRouter(prefix="/api/channels", tags=["channels"])
+router = APIRouter(prefix="/channels", tags=["channels"])
 
 
 class ChannelStatusResponse(BaseModel):

backend/app/gateway/routers/feedback.py

@@ -16,7 +16,7 @@ from app.gateway.authz import require_permission
 from app.gateway.deps import get_current_user, get_feedback_repo, get_run_store
 
 logger = logging.getLogger(__name__)
-router = APIRouter(prefix="/api/threads", tags=["feedback"])
+router = APIRouter(prefix="/threads", tags=["feedback"])
 
 
 # ---------------------------------------------------------------------------

backend/app/gateway/routers/mcp.py

@@ -9,7 +9,7 @@ from pydantic import BaseModel, Field
 from deerflow.config.extensions_config import ExtensionsConfig, get_extensions_config, reload_extensions_config
 
 logger = logging.getLogger(__name__)
-router = APIRouter(prefix="/api", tags=["mcp"])
+router = APIRouter(tags=["mcp"])
 
 
 class McpOAuthConfigResponse(BaseModel):

backend/app/gateway/routers/memory.py

@@ -15,7 +15,7 @@ from deerflow.agents.memory.updater import (
 from deerflow.config.memory_config import get_memory_config
 from deerflow.runtime.user_context import get_effective_user_id
 
-router = APIRouter(prefix="/api", tags=["memory"])
+router = APIRouter(tags=["memory"])
 
 
 class ContextSection(BaseModel):

backend/app/gateway/routers/models.py

@@ -4,7 +4,7 @@ from pydantic import BaseModel, Field
 from app.gateway.deps import get_config
 from deerflow.config.app_config import AppConfig
 
-router = APIRouter(prefix="/api", tags=["models"])
+router = APIRouter(tags=["models"])
 
 
 class ModelResponse(BaseModel):

backend/app/gateway/routers/runs.py

@@ -21,7 +21,7 @@ from app.gateway.services import sse_consumer, start_run
 from deerflow.runtime import serialize_channel_values
 
 logger = logging.getLogger(__name__)
-router = APIRouter(prefix="/api/runs", tags=["runs"])
+router = APIRouter(prefix="/runs", tags=["runs"])
 
 
 def _resolve_thread_id(body: RunCreateRequest) -> str:

backend/app/gateway/routers/skills.py

@@ -18,7 +18,7 @@ from deerflow.skills.types import SKILL_MD_FILE, SkillCategory
 
 logger = logging.getLogger(__name__)
 
-router = APIRouter(prefix="/api", tags=["skills"])
+router = APIRouter(tags=["skills"])
 
 
 class SkillResponse(BaseModel):

backend/app/gateway/routers/suggestions.py

@@ -12,7 +12,7 @@ from deerflow.models import create_chat_model
 
 logger = logging.getLogger(__name__)
 
-router = APIRouter(prefix="/api", tags=["suggestions"])
+router = APIRouter(tags=["suggestions"])
 
 
 class SuggestionMessage(BaseModel):

backend/app/gateway/routers/thread_runs.py

@@ -25,7 +25,7 @@ from app.gateway.services import sse_consumer, start_run
 from deerflow.runtime import RunRecord, serialize_channel_values
 
 logger = logging.getLogger(__name__)
-router = APIRouter(prefix="/api/threads", tags=["runs"])
+router = APIRouter(prefix="/threads", tags=["runs"])
 
 
 # ---------------------------------------------------------------------------

backend/app/gateway/routers/threads.py

@@ -29,7 +29,7 @@ from deerflow.runtime.user_context import get_effective_user_id
 from deerflow.utils.time import coerce_iso, now_iso
 
 logger = logging.getLogger(__name__)
-router = APIRouter(prefix="/api/threads", tags=["threads"])
+router = APIRouter(prefix="/threads", tags=["threads"])
 
 
 # Metadata keys that the server controls; clients are not allowed to set

backend/app/gateway/routers/uploads.py

@@ -30,7 +30,7 @@ from deerflow.utils.file_conversion import CONVERTIBLE_EXTENSIONS, convert_file_
 
 logger = logging.getLogger(__name__)
 
-router = APIRouter(prefix="/api/threads/{thread_id}/uploads", tags=["uploads"])
+router = APIRouter(prefix="/threads/{thread_id}/uploads", tags=["uploads"])
 
 UPLOAD_CHUNK_SIZE = 8192
 DEFAULT_MAX_FILES = 10