Add question-reframing guidance to CLAUDE.md; commit accumulated project files

- CLAUDE.md: add "Question the question" and "One clarifying question" rules
  to Tone and Interaction — XY problem detection, false premise checks, and
  explicit reframe pattern before answering
- Add claude/ detail-file directory (topic docs referenced from CLAUDE.md)
- Add ABOUT.md, FUTURE.md
- Update memory/, scripts/, settings.yaml with accumulated session changes

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

claude/plan-mode.md

@@ -0,0 +1,23 @@
+# Plan Mode
+
+When working in plan mode (`permission_mode: plan`):
+
+**Before calling `ExitPlanMode`**, always write the complete plan to a file in the project root:
+
+- **Filename:** `[MILESTONE]-[PURPOSE]-PLAN.md` — e.g. `M2-auth-PLAN.md`, `M3-monitoring-PLAN.md`
+  - MILESTONE: the milestone identifier (e.g. `M2`) or a short label if not milestone-scoped (e.g. `initial`)
+  - PURPOSE: a short kebab-case description of what the plan covers
+- **Contents:** the full plan as developed in the planning conversation — steps, decisions, rationale, open questions
+- **Location:** project root (same directory as CLAUDE.md)
+
+This file becomes the implementation reference for the session that follows plan mode.
+
+## Keep the plan updated during implementation
+
+After each phase or significant step, update PLAN.md:
+- Mark the phase/step status as **Complete**
+- Add key commits, references, or artifacts produced
+- Document deviations from the original plan (what changed and why)
+- Note verification results
+
+This keeps the plan accurate as a living document — useful for resuming across sessions, reflecting on the milestone, and understanding what actually happened vs. what was planned.