de-meta the system prompts; method leads the composition (owner, 2026-09-27)

The owner's capture-vs-composition check confirmed the wire sends exactly
what composes (byte-identical save the nodeId paragraph ebfe058 had since
changed). This wave removes the implementation meta that leaked into the
prompts and reorders so the method carries weight:

- base: owner's new opener verbatim (install understanding; the
  understanding definition — which absorbs the old 'Understanding is
  structure' paragraph); Voice moved in from shared/10 (deleted); the
  philosophy keeps edge-dependence + logistics ('standard learning'
  dropped per owner); intro's two-agents/fragments sentence gone.
- teacher/05-method opens with the owner's methodology bridge ('No other
  teaching methods come close') — paragraph 3 of the opener, placed here
  so the shared base never points the prober at methodology it doesn't
  carry.
- deleted: teacher/60-probing-in-brief (self-evident from shared history;
  its mid-lesson mini-probe move salvaged into 20-teaching as one
  sentence), the 'Session shape — the durable artifact' section
  (extraction-pipeline meta), the fragments-meta lines in shared/20 and
  05-method, 'the transcript's seam' phrasing, prober's 'the teacher
  that takes over' / 'the handoff is automatic'.
- composition reorder (listSourceSegments): base -> the agent's own
  fragments -> shared/ appendix. Teacher method now starts at 12% in
  (was 62%); prober doctrine at 34%. shared/20 opens with the owner's
  decision rule (quiz only for known-correct-answer, ask for everything
  else).
- HANDOFF_TEXT: the owner's user-message version — first-person, paces
  the planning (unconditional truths, motivated derivations), ends at
  plan_init + accept-or-changes.

Teacher 31.4k -> 28.7k chars; prober 10.0k -> 9.6k. Gates: typecheck 0,
1018/1018, lint clean, build green. (Suite runs 16s; the earlier 10-min
timeout was stale node_modules after master's df1328e 0.87.1 sync —
npm install fixed it.)

src/agent/teacher-agent.ts

@@ -29,10 +29,12 @@ import { toLlmMessages } from "../core/native-messages.ts";
  * deterministic lessons (see tests/chat-flow.test.ts).
  *
  * System prompts are COMPOSED per agent: system-prompt.md (the shared base:
- * philosophy, accuracy, quiz construction, question tools, formatting) +
- * every numeric-prefix fragment in that agent's directory
- * (src/agent/prompts/prober/ or src/agent/prompts/teacher/), in sorted
- * filename order, joined with `---` separators.
+ * agent, voice, philosophy, accuracy) + every numeric-prefix fragment in
+ * that agent's directory (src/agent/prompts/prober/ or
+ * src/agent/prompts/teacher/), in sorted filename order, then the shared/
+ * fragments as a trailing appendix (question tools, learner files,
+ * formatting) — the 2026-09-27 reorder: the agent's job and method lead,
+ * the mechanics trail. Joined with `---` separators.
  *
  * ONLY numeric-prefix files load — the loader enforces the convention, so
  * non-fragment documentation (README.md, …) can live in the directories