Pre-push review: worktree-settings-commit-hash

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8dd085a..85aabb6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,6 +14,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - `prism-notes-js` spec for a self-contained single-file JavaScript library that adds basic note-taking and copy-as-markdown to any HTML page (personal-use companion artifact; not part of the Prism Swift app). Smolspec, decision log, and 8 implementation tasks live under `specs/prism-notes-js/`.
 - `prism-notes-js/prism-notes.js` implementation (~1500 lines, single ES2022 IIFE, no dependencies). Selecting text shows a "+ Add note" pill; saving creates a note anchored via a text-quote selector (prefix/exact/suffix + position hint) and a SHA-256 document-text hash. Notes persist in `localStorage` keyed by `pathname+search`, re-highlight via the CSS Custom Highlight API on reload, and surface in a side panel with a "Copy as Markdown" footer button (clipboard write with a textarea-fallback modal). Includes `prism-notes-js/README.md` documenting the three install paths (script tag, bookmarklet for permissive CSP, DevTools paste for strict CSP) and `prism-notes-js/test-page.html` as a manual-test fixture. Personal-use scope: no sync, no sharing, no import, no Shadow DOM, no accessibility commitments.
 - `footnote-badge-a11y` smolspec (T-1036) for VoiceOver discoverability and operability of inline footnote badges, covering paragraph-level accessibility-label rebuild and per-paragraph accessibility actions in `HighlightedInlineText`. Decision log captures the pivot away from a Textual fork change to a single-file view-layer approach. Five linearly-dependent tasks live under `specs/footnote-badge-a11y/`.
+- **Debug-only:** Settings → About now shows a "Build" row beneath "Version" with the short git commit hash the build was produced from, suffixed `-dirty` when the working tree had uncommitted changes (and `unknown` when built outside a git checkout). A new `Tools/stamp-commit-hash.sh` build phase writes `GitCommit` into the bundled `Info.plist` using `PlistBuddy`; the script bails early when `CONFIGURATION` isn't `Debug`, so Release/TestFlight/App Store builds never carry the key. The Settings UI and `Bundle.appCommitHash` accessor are wrapped in `#if DEBUG` as a second line of defence. The phase is marked always-out-of-date so the Debug value refreshes on every build.
 - Footnote badges are now discoverable and operable for VoiceOver (T-1036). New `FootnoteAccessibility` helper (`prism/Services/FootnoteAccessibility.swift`) extracts unique footnote references in first-occurrence order and rebuilds a paragraph-level accessibility label that substitutes each resolvable `[^id]` with the localised inline phrase "footnote N". `HighlightedInlineText` applies a private `FootnoteAccessibilityModifier` that overrides the paragraph's accessibility label and exposes one "Show footnote N" action per unique reference via `.accessibilityActions { … }`. Each action opens the existing `prism://footnote/{id}` URL through `@Environment(\.openURL)`, reusing the tap-routing flow already wired in `DocumentReaderView`. The modifier is a no-op when no resolvable references are present, so paragraphs without footnotes keep their auto-derived narration. New localised keys `a11y.footnote.inline %lld` and `a11y.footnote.action %lld` added to `prism/Localizable.xcstrings`. Helpers covered by new unit tests in `prismTests/FootnoteAccessibilityTests.swift`.

 ### Fixed

diff --git a/Tools/stamp-commit-hash.sh b/Tools/stamp-commit-hash.sh
new file mode 100755
index 0000000..dcb5131
--- /dev/null
+++ b/Tools/stamp-commit-hash.sh
@@ -0,0 +1,36 @@
+#!/bin/sh
+# Stamps the current git commit hash into the bundled Info.plist as the
+# `GitCommit` key, so the running app can show which commit it was built from.
+# Falls back to "unknown" outside a git working tree.
+
+set -eu
+
+# Debug builds only — we don't want to leak a git commit hash to end users
+# in TestFlight / App Store archives. Release builds skip the stamp; the
+# Settings UI is `#if DEBUG`-gated as a second layer of defence.
+if [ "${CONFIGURATION:-}" != "Debug" ]; then
+    echo "stamp-commit-hash: skipping (CONFIGURATION=${CONFIGURATION:-unset})"
+    exit 0
+fi
+
+PLIST_PATH="${TARGET_BUILD_DIR}/${INFOPLIST_PATH}"
+
+if [ ! -f "${PLIST_PATH}" ]; then
+    echo "stamp-commit-hash: Info.plist not found at ${PLIST_PATH}" >&2
+    exit 0
+fi
+
+cd "${SRCROOT}"
+
+if COMMIT=$(git rev-parse --short HEAD 2>/dev/null); then
+    if [ -n "$(git status --porcelain 2>/dev/null)" ]; then
+        COMMIT="${COMMIT}-dirty"
+    fi
+else
+    COMMIT="unknown"
+fi
+
+/usr/libexec/PlistBuddy -c "Delete :GitCommit" "${PLIST_PATH}" 2>/dev/null || true
+/usr/libexec/PlistBuddy -c "Add :GitCommit string ${COMMIT}" "${PLIST_PATH}"
+
+echo "stamp-commit-hash: GitCommit=${COMMIT}"

diff --git a/prism.xcodeproj/project.pbxproj b/prism.xcodeproj/project.pbxproj
index 80fee3e..7cf486c 100644
--- a/prism.xcodeproj/project.pbxproj
+++ b/prism.xcodeproj/project.pbxproj
@@ -129,6 +129,7 @@
 				D49C76612F0CC12F00CE740B /* Frameworks */,
 				D49C76622F0CC12F00CE740B /* Resources */,
 				D4A678812FA80000005E8A40 /* Localisation: install compiled strings */,
+				D4A678822FA80000005E8A40 /* Stamp git commit hash */,
 			);
 			buildRules = (
 			);
@@ -324,6 +325,21 @@
 			shellPath = /bin/sh;
 			shellScript = "set -euo pipefail\nINSTALL_DIR=\"${TARGET_BUILD_DIR}/${UNLOCALIZED_RESOURCES_FOLDER_PATH}\"\nmkdir -p \"${INSTALL_DIR}\"\nfor locale in en en-AU en-GB en-US; do\n    mkdir -p \"${INSTALL_DIR}/${locale}.lproj\"\n    for ext in strings stringsdict; do\n        src=\"${DERIVED_FILE_DIR}/CompiledStrings/${locale}.lproj/Localizable.${ext}\"\n        if [ -f \"${src}\" ]; then\n            /bin/cp \"${src}\" \"${INSTALL_DIR}/${locale}.lproj/Localizable.${ext}\"\n        fi\n    done\ndone\n";
 		};
+		D4A678822FA80000005E8A40 /* Stamp git commit hash */ = {
+			isa = PBXShellScriptBuildPhase;
+			alwaysOutOfDate = 1;
+			buildActionMask = 2147483647;
+			files = (
+			);
+			inputPaths = (
+			);
+			name = "Stamp git commit hash";
+			outputPaths = (
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+			shellPath = /bin/sh;
+			shellScript = "set -eu\n/bin/sh \"${SRCROOT}/Tools/stamp-commit-hash.sh\"\n";
+		};
 /* End PBXShellScriptBuildPhase section */

 /* Begin PBXSourcesBuildPhase section */

diff --git a/prism/Settings/SettingsView.swift b/prism/Settings/SettingsView.swift
index 202f356..4de8b24 100644
--- a/prism/Settings/SettingsView.swift
+++ b/prism/Settings/SettingsView.swift
@@ -490,6 +490,15 @@ struct SettingsView: View {
     private var aboutSection: some View {
         Section {
             LabeledContent("Version", value: Bundle.main.appVersion)
+            #if DEBUG
+            if let commit = Bundle.main.appCommitHash {
+                LabeledContent("Build", value: commit)
+                    .accessibilityLabel(LocalizedStringKey("Build commit hash"))
+                    .accessibilityValue(commit)
+                    .textSelection(.enabled)
+                    .monospaced()
+            }
+            #endif
             Link(destination: URL(string: "https://github.com/ArjenSchwarz/prism")!) {
                 HStack {
                     Text("Source Code")
@@ -565,6 +574,19 @@ extension Bundle {
     var appVersion: String {
         (infoDictionary?["CFBundleShortVersionString"] as? String) ?? "1.0"
     }
+
+    #if DEBUG
+    /// Short git commit hash stamped into the Debug bundle at build time by
+    /// `Tools/stamp-commit-hash.sh`. Returns `nil` when the build wasn't
+    /// stamped (e.g. the build phase didn't run) and "unknown" when the build
+    /// happened outside a git working tree. Debug-only: Release builds skip
+    /// the stamp so the hash never ships to end users.
+    var appCommitHash: String? {
+        guard let value = infoDictionary?["GitCommit"] as? String,
+              !value.isEmpty else { return nil }
+        return value
+    }
+    #endif
 }

 #Preview {