Show unseen Server commits after login.

Bake first-parent git log at Server build and remember the SHA in a browser cookie.

Co-authored-by: Cursor <cursoragent@cursor.com>

tools/embed-changelog.sh

@@ -0,0 +1,23 @@
+#!/bin/sh
+# UTF-8 first-parent log for HSchool.Server. Keep in sync with embed-changelog.ps1.
+set -e
+RepoRoot=$1
+Output=$2
+if [ -z "$RepoRoot" ] || [ -z "$Output" ]; then
+  echo "usage: embed-changelog.sh <repo-root> <output>" >&2
+  exit 1
+fi
+mkdir -p "$(dirname "$Output")"
+sha=
+log=
+if sha=$(git -C "$RepoRoot" rev-parse HEAD 2>/dev/null) && [ "${#sha}" -eq 40 ]; then
+  log=$(git -C "$RepoRoot" -c core.quotepath=false log --first-parent --encoding=UTF-8 --pretty=format:%H%x1f%cI%x1f%s) || log=
+else
+  sha=
+fi
+{
+  printf '%s\n' "$sha"
+  if [ -n "$log" ]; then
+    printf '%s\n' "$log"
+  fi
+} > "$Output"