wave 7: the prober reads its map — graph-context injection dies whole

The owner's zero-configuration ruling (2026-09-23): nothing configures
the graph beyond chat models. The prior-knowledge injection — its budget
dial, its runner, its marker part, its dock/dispatch entries — is
removed across all bands; the prober now reads the learner's persistent
knowledge map on demand through two gated tools instead:

- list_sessions: every birth session, names + kinds + counts + dates
  (graphSessionIndex, Platform's core seam)
- list_propositions(session): what was born there + the session's own
  latest understanding level + that evaluation's date
  (graphSessionPropositions) — names/levels/dating ONLY, no statement
  text (owner ruling: the map's organization is the prober's business,
  its prose is not)

Registered via createProberTools when chat-handler passes graphStore
(the graphToolsEnabled gate decided server-side, per-turn fresh); the
prober doctrine gains the map-review nudge at session start.

Also: runner's JobKind special-casing collapses (KIND_ROLE/KIND_RUNNERS
are plain records again), semantic-clusters.ts dies with its test, the
embedder dep's doc tells the wave-7 stub story, and ports.ts's
readClusterLabels/readNamingRuns surface stays untouched for Platform's
ledger-port interlude.

848/848 tests, typecheck/lint/build green.

components/activity-dock.tsx

@@ -1,7 +1,7 @@
 "use client";
 
 import { createContext, useCallback, useContext, useEffect, useMemo, useRef, useState } from "react";
-import { ActivityIcon, BookOpenIcon, BotIcon, FileTextIcon, PenToolIcon, PlayIcon, SearchIcon, SquareIcon, WaypointsIcon } from "lucide-react";
+import { ActivityIcon, BotIcon, FileTextIcon, PenToolIcon, PlayIcon, SearchIcon, SquareIcon, WaypointsIcon } from "lucide-react";
 import { cn } from "@/lib/utils";
 import type { CallUsage, JobKind, JobRecord } from "@/src/core";
 import { CONTEXT_LIMITS, isModelsRefusal, jobCost } from "@/src/core";
@@ -236,7 +236,6 @@ const KIND_ICON: Record<JobKind, typeof SearchIcon> = {
 	demo: PlayIcon,
 	visual: PenToolIcon,
 	pdf: FileTextIcon, // sources v0 — type-forced entry (JobKind grew "pdf")
-	"graph-context": BookOpenIcon,
 };
 
 /** Abort states per blob id: pending (fired) / failed (backend absent). */
@@ -353,9 +352,7 @@ function ActivityBlobRow({
 						? "Figure maker"
 						: blob.jobKind === "pdf"
 							? "PDF reader"
-							: blob.jobKind === "graph-context"
-								? "Graph context"
-								: "Sub-agent";
+							: "Sub-agent";
 	return (
 		<div
 			data-testid={`activity-blob-${blob.process}`}