The tier axis comes out of the git stack — compose unconditional, postures mode-driven

HistoryStore.compose(boardRoot📒) returns non-optional and runs for
every session — the nil the gate produced was the only nil it ever had.
makeHistoryProvider is a one-axis decision: git-mode boards bind the git
provider, everything else native, in every tier; Session.tier stays
recorded, dormant. BoardGitSection shrinks to the four mode postures
(.absent and .proPointer die, BoardGitNote and the .git probe with them);
every board carries all three popover tabs (BoardInfoTab.available
retired); the titlebar branch shows on any git-mode board; the settings
sheet and card History section stop reading tier. InertGitTests is
repurposed as UntouchedGitTests — the file layer still never opens .git,
now load-bearing for mode-none boards. The accessibility audit reaches the
settings sheet at last: the fixture board hosts it in every tier, so the
free-fixture disabled-row test becomes an open-and-audit test.

Claude-Session: https://claude.ai/code/session_01SR4XGjmBE16ZUYWpfFHXwY

Kanban/Git/GitAutoCommitter.swift

@@ -44,12 +44,15 @@ public struct GitLandedWindow: Sendable, Equatable {
 /// **Every settled change becomes a commit** (06-history-undo.md ▸ Rules ▸ Auto-commit), debounced
 /// past drag and typing churn, on git-mode boards and nowhere else.
 ///
-/// ### Structurally unreachable off Pro
+/// ### Structurally unreachable on a board with no repository
 ///
-/// One of these exists per `HistoryStore` in mode `git`, and a `HistoryStore` exists only under Pro
-/// (`HistoryStore.compose` is the tier gate). The free tier therefore has no committer to disable,
-/// no debounce to cancel and no `.git` to touch — 12-editions.md's inert posture as a shape rather
-/// than as a flag, which `InertGitTests` pins against real bytes.
+/// One of these exists per `HistoryStore` in mode `git` and nowhere else. Until the 2026-08-07 pivot
+/// there was a second gate above it — a `HistoryStore` existed only under Pro — and that one is gone
+/// (12-editions.md ▸ PIVOT 2026-08-07: git left the paywall, and every tier composes the git stack
+/// on git-mode boards). What remains is the stronger of the two anyway, because it never depended on
+/// a subscription: git is **opt-in per board** (06 ▸ Rules), so a board the user never added git to
+/// detects `none`, composes no committer, and has no debounce to cancel and no `.git` to touch. The
+/// file layer's own indifference to `.git` is pinned against real bytes by `UntouchedGitTests`.
 ///
 /// ### What arms it
 ///