refactor: fold the detail and diff views' flags into a mode and a phase

.claude/rules/go-style.md

@@ -67,11 +67,6 @@ paths:
 
 `.claude/rules/*.md` への参照は別で、これは今も有効な規約を指しているので残してよい。
 
-<!-- TRANSIENT(Part2 作業順 8): spec 参照を消したらこの注記を消す -->
-> **2026-09-07 時点で、非テストコードに `spec N` / `Task N` の参照が 26 箇所ある。**
-> 消す作業は Phase 2 立て直しの作業順 8（Part 2 の実装計画で扱う）。
-> **新しく書くコードでこれを言い訳にしない。**
-
 良い例。`gh api` が `--repo` を受け付けないという外部の事情は、コードを読んでも分からない。
 
 ```go

.claude/rules/tui.md

@@ -66,12 +66,6 @@ const (
 
 エラー文字列も mode ごとに分けて持たない。どこに描くかは mode が決める。
 
-<!-- TRANSIENT(Part2 作業順 6): bool を enum に畳んだらこの注記を消す -->
-> **2026-09-07 時点で `detail` と `diff` がこれを破っている。**
-> `detail.Model` は bool 10 個 + エラー文字列 3 本を持つ。畳む作業は
-> Phase 2 立て直しの作業順 6（Part 2 の実装計画で扱う）。
-> **新しく書くビューでこれを言い訳にしない。**
-
 ## 表示幅
 
 **日本語は 1 文字が 2 桁を占める。** 桁数を数えるときは必ず

docs/superpowers/specs/2026-09-06-phase2-remediation-design.md

@@ -557,6 +557,17 @@ Bubble Tea を起動せずに検証する。
 4 と 6 は同じファイルを触るため、4 を完了してから 6 に入る。
 各段階で `make check` を通し、通らない状態でコミットしない。
 
+> **2026-09-07 追記。** Part 2（作業順 6〜9）は **9 → 6 → 7 → 8** の順で実施した。
+> 9 のシナリオテストは 6 が書き換える遷移をそのまま通るので、現行コードの上で
+> 先に書けば 6 と 7 の回帰ネットになる。あわせて、6 の前に未収録の golden
+> （`detail` の compose / picker / loading / エラー行、`diff` の各オーバーレイ）を
+> 録った。「golden 不変で等価性を確認する」は録れているセルにしか効かないため。
+>
+> §4.4 の表から 3 点変えた。`diff` の `loading` は畳まない（`c` / `v` / `X` は
+> レビューコンテキストでゲートされており、差分の取得中でもオーバーレイは開ける）。
+> 送信中は `review.Model` の `sending` に任せ、`phase` に写さない。
+> `picker` が持っていた 4 本目のエラー文字列も 1 本に畳んだ。
+
 ## 7. スコープ外
 
 - **DI コンテナは作らない。** `cmd/octoscope` で `cli.New → usecase.New → app.New` と

internal/gh/review.go

@@ -38,7 +38,7 @@ func (t ReviewThread) Pending() bool {
 
 // Collapsed reports whether the thread is drawn as a count rather than in
 // full. Settled conversations must not push the code they were about off the
-// screen (spec 4.4.1).
+// screen.
 func (t ReviewThread) Collapsed() bool { return t.Resolved || t.Outdated }
 
 // PendingComment is a line comment on its way to GitHub.

internal/tui/app/app.go

@@ -36,7 +36,7 @@ type Options struct {
 	// the working directory is a subprocess, and doing it before the UI
 	// started left the terminal blank for as long as it took. The root asks
 	// as soon as it has a size, and the Repos tab appears when the answer
-	// arrives (spec 3.4).
+	// arrives.
 	HasRepo bool
 }
 
@@ -166,19 +166,7 @@ func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 	case tea.MouseMsg:
 		return m.handleMouse(msg)
 	case repoResolvedMsg:
-		if !msg.found {
-			m.repoLookupTimedOut = msg.timedOut
-			return m, nil
-		}
-		m.opts.HasRepo = true
-		// broadcast skips the list until this point, so it never saw the
-		// WindowSizeMsg that told the others how wide they are: an unsized
-		// list clips nothing and runs off the terminal.
-		m.repo, _ = m.repo.Update(tea.WindowSizeMsg{
-			Width:  m.width,
-			Height: max(m.height-tabRowHeight, 1),
-		})
-		return m, m.repo.Init()
+		return m.repoResolved(msg)
 	case work.OpenDetailMsg:
 		return m.openDetail(msg.Ref)
 	case repo.OpenDetailMsg:
@@ -200,40 +188,67 @@ func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 	case repo.ErrorMsg:
 		return m.fail(msg.Err)
 	case detail.ErrorMsg:
-		// The detail view keeps requests in flight after the user leaves it.
-		// Their failures must not drag a closed view's error onto the screen.
-		if !m.has(overlayDetail) {
-			return m, nil
-		}
-		return m.failOverlay(msg.Err, overlayDetail)
+		return m.detailFailed(msg)
 	case diff.ErrorMsg:
-		// Same rule as detail.ErrorMsg: a request outlives the view that
-		// started it, and its failure must not reach the error screen once
-		// the diff is no longer on the stack.
-		if !m.has(overlayDiff) {
-			return m, nil
-		}
-		return m.failOverlay(msg.Err, overlayDiff)
+		return m.diffFailed(msg)
 	case review.SubmittedMsg:
-		// detail and diff each refetch their own PR when a review goes out
-		// (broadcast below reaches them); the board and the Repos list have
-		// no popup of their own to notice from, so the root refreshes them
-		// (spec 4.4.2).
-		next, cmd := m.broadcast(msg)
-		m = next.(Model)
-		var workCmd tea.Cmd
-		m.work, workCmd = m.work.Refresh()
-		cmds := []tea.Cmd{cmd, workCmd}
-		if m.opts.HasRepo {
-			var repoCmd tea.Cmd
-			m.repo, repoCmd = m.repo.Refresh()
-			cmds = append(cmds, repoCmd)
-		}
-		return m, tea.Batch(cmds...)
+		return m.reviewSubmitted(msg)
 	}
 	return m.broadcast(msg)
 }
 
+func (m Model) repoResolved(msg repoResolvedMsg) (tea.Model, tea.Cmd) {
+	if !msg.found {
+		m.repoLookupTimedOut = msg.timedOut
+		return m, nil
+	}
+	m.opts.HasRepo = true
+	// broadcast skips the list until this point, so it never saw the
+	// WindowSizeMsg that told the others how wide they are: an unsized
+	// list clips nothing and runs off the terminal.
+	m.repo, _ = m.repo.Update(tea.WindowSizeMsg{
+		Width:  m.width,
+		Height: max(m.height-tabRowHeight, 1),
+	})
+	return m, m.repo.Init()
+}
+
+// The detail view keeps requests in flight after the user leaves it.
+// Their failures must not drag a closed view's error onto the screen.
+func (m Model) detailFailed(msg detail.ErrorMsg) (tea.Model, tea.Cmd) {
+	if !m.has(overlayDetail) {
+		return m, nil
+	}
+	return m.failOverlay(msg.Err, overlayDetail)
+}
+
+// Same rule as detail.ErrorMsg: a request outlives the view that
+// started it, and its failure must not reach the error screen once
+// the diff is no longer on the stack.
+func (m Model) diffFailed(msg diff.ErrorMsg) (tea.Model, tea.Cmd) {
+	if !m.has(overlayDiff) {
+		return m, nil
+	}
+	return m.failOverlay(msg.Err, overlayDiff)
+}
+
+// detail and diff each refetch their own PR when a review goes out
+// (broadcast below reaches them); the board and the Repos list have
+// no popup of their own to notice from, so the root refreshes them.
+func (m Model) reviewSubmitted(msg review.SubmittedMsg) (tea.Model, tea.Cmd) {
+	next, cmd := m.broadcast(msg)
+	m = next.(Model)
+	var workCmd tea.Cmd
+	m.work, workCmd = m.work.Refresh()
+	cmds := []tea.Cmd{cmd, workCmd}
+	if m.opts.HasRepo {
+		var repoCmd tea.Cmd
+		m.repo, repoCmd = m.repo.Refresh()
+		cmds = append(cmds, repoCmd)
+	}
+	return m, tea.Batch(cmds...)
+}
+
 // has reports whether o is anywhere on the stack, not only on top: the
 // detail view keeps fetching while the diff is drawn over it.
 func (m Model) has(o overlay) bool {

internal/tui/app/render.go

@@ -26,7 +26,7 @@ func (m Model) View() tea.View {
 	v := tea.NewView(content)
 	v.AltScreen = true
 	// Nothing else turns the mouse on: without this the terminal reports no
-	// clicks and no wheel at all (spec 4).
+	// clicks and no wheel at all.
 	v.MouseMode = tea.MouseModeCellMotion
 	return v
 }
@@ -39,9 +39,8 @@ func (m Model) activeTab() string {
 }
 
 // tabLabels names the tabs on offer, in display order. Without a target
-// repository the Repos tab is not offered at all (spec 3.4). Both the tab row
-// and the mouse hit-test read this, so they cannot disagree about where a
-// label sits.
+// repository the Repos tab is not offered at all. Both the tab row and the
+// mouse hit-test read this, so they cannot disagree about where a label sits.
 func (m Model) tabLabels() []string {
 	labels := []string{"1 " + i18n.T("tab.work")}
 	if m.opts.HasRepo {