chore(contextual): purge residual floating WsFrame defs + output_formatter branch

After M6.5 deletion of run_floating_stream and the frame dispatch,
WsFrameType.floating_request/floating_domain, WsFloatingRequest,
WsFloatingDomain, WsFloatingScope, WsDomain, and the StreamFormatter's
floating_domain branch were left as dead protocol surface. Remove them,
along with the corresponding test cases in test_schemas_v3.py and
test_output_formatter.py.

app/schemas/__init__.py

@@ -73,11 +73,9 @@ class WsFrameType(str, Enum):
     device_hello = "device_hello"
     # ── v3 frame types ─────────────────────────────────────────────────
     home_request = "home_request"
-    floating_request = "floating_request"
     stream_start = "stream_start"
     stream_text = "stream_text"
     stream_end = "stream_end"
-    floating_domain = "floating_domain"
     data_request = "data_request"
     data_response = "data_response"
     mutation = "mutation"
@@ -165,13 +163,6 @@ class FormatPrefsModel(BaseModel):
     now_iso: str = ""
 
 
-class WsFloatingScope(BaseModel):
-    """Scope for a floating request — narrows the agent to a specific entity."""
-
-    type: Literal["task", "project", "note", "timeline"]
-    id: str | None = None
-
-
 class WsHomeRequest(BaseModel):
     """Client → Server: Home chat message."""
 
@@ -181,15 +172,6 @@ class WsHomeRequest(BaseModel):
     format_prefs: FormatPrefsModel | None = None
 
 
-class WsFloatingRequest(BaseModel):
-    """Client → Server: Floating chat message scoped to an entity."""
-
-    type: Literal[WsFrameType.floating_request] = WsFrameType.floating_request
-    message: str
-    scope: WsFloatingScope
-    format_prefs: FormatPrefsModel | None = None
-
-
 class WsBriefRequest(BaseModel):
     """Client → Server: Request a plain-text brief (home or project)."""
 
@@ -225,22 +207,6 @@ class WsStreamEnd(BaseModel):
     mutations: list[dict[str, Any]] | None = None
 
 
-class WsDomain(BaseModel):
-    """Structured floating domain payload for UI routing decisions."""
-
-    type: Literal["task", "timeline", "project", "node"]
-    id: str | None = None
-    section: Literal["task", "timeline", "note"] | None = None
-
-
-class WsFloatingDomain(BaseModel):
-    """Server → Client: domain determined for a floating request."""
-
-    type: Literal[WsFrameType.floating_domain] = WsFrameType.floating_domain
-    request_id: str
-    domain: WsDomain
-
-
 # ── Agent Config V2 ───────────────────────────────────────────────────