fix: verdict death — plan→teach seam inferred from first nodeId-tagged quiz

The Accept/Decline verdict gate is gone (owner ruling 2026-09-26):
presenting the plan ends the teacher's turn; the learner's next message
is a natural reply. Teaching begins at the first quiz call tagged with a
nodeId (probe quizzes carry none) — both folds (view phaseAt3, native
phaseAt3Lh) advance on the call itself, and the teach divider renders
before that whole assistant block. No backwards compat: verdict markers,
the verdict input event, optimistic appends, composer buttons, and
projection all deleted; prompts and docs rewritten to the natural flow.

src/agent/teacher-agent.ts

@@ -181,7 +181,7 @@ function baseAgentOptions(kind: AgentKind, opts: AgentBuildOptions, tools: Agent
 		steeringMode: "all",
 		// Wave B (owner-approved 2026-09-26): the model-facing conversion is
 		// THE app seam — markers flatten to their canonical user text
-		// (verdictText / HANDOFF_TEXT / steer text, all single-sourced),
+		// (HANDOFF_TEXT / steer text, all single-sourced),
 		// UI-only markers (plan-block) drop, the app's id fields strip, and
 		// an abort's dangling question call gets its INTERRUPTED result. It
 		// must never throw (pi's convertToLlm contract).