merge: origin/main into next for the 0.0.50 integration line

next carries 108 commits main lacks; main carries 23 next lacks, including
the MOSAIC_GIT_IDENTITY work that per-agent git credentials depend on.
Neither stream alone can ship 0.0.50: next drops identity, main drops
everything since the split.

Conflicts and how they were settled:
- packages/mosaic/package.json test:framework-shell -- union. Neither side
  removed an entry; next added 6, main added 8, one shared. 50 total.
- framework/tools/git/pr-merge.sh -- next's form. It permits base 'main' or
  'next'; main's permits 'main' only, and the release line targets next.
- framework/tools/git/test-ci-queue-wait-tristate.sh -- both sides appended
  to the same region (next: merge-readiness assertions; main: a real-clock
  watchdog control). Kept both.
- docs/SITEMAP.md -- both sides appended distinct sections. Kept both.

packages/mosaic/framework/tools/_scripts/mosaic-doctor

@@ -153,6 +153,38 @@ warn_if_symlink_tree_present() {
 
 echo "[mosaic-doctor] Mosaic home: $MOSAIC_HOME"
 
+# Compare the framework tools that this CLI/package ships with the deployed
+# ~/.config copy that direct wrappers and systemd units actually execute. Doctor
+# is the right boundary: observational, operator-invoked, and already designed
+# to report drift without mutating live tooling or restarting active seats.
+framework_drift_checker="$(cd -- "$(dirname -- "$0")/../quality/scripts" && pwd)/framework-drift-check.py"
+if [[ -f "$framework_drift_checker" ]]; then
+  echo "[mosaic-doctor] Checking installed framework-tool drift..."
+  drift_timeout="${MOSAIC_DOCTOR_DRIFT_TIMEOUT_SEC:-15}"
+  if ! [[ "$drift_timeout" =~ ^[1-9][0-9]*$ ]]; then
+    warn "Invalid MOSAIC_DOCTOR_DRIFT_TIMEOUT_SEC='$drift_timeout' (expected positive integer); using 15s"
+    drift_timeout=15
+  fi
+  if command -v timeout >/dev/null 2>&1; then
+    set +e
+    timeout -s TERM -k 2 "${drift_timeout}s" \
+      python3 "$framework_drift_checker" --installed-root "$MOSAIC_HOME/tools"
+    drift_rc=$?
+    set -e
+    if [[ "$drift_rc" -eq 0 ]]; then
+      pass "Installed framework tools match shipped source"
+    elif [[ "$drift_rc" -eq 124 || "$drift_rc" -eq 137 || "$drift_rc" -eq 143 ]]; then
+      warn "CANNOT_ASSERT framework drift checker timed out after ${drift_timeout}s; continuing remaining doctor checks"
+    else
+      warn "Installed framework-tool drift detected (checker exit $drift_rc; no files changed)"
+    fi
+  else
+    warn "CANNOT_ASSERT timeout utility unavailable; refusing unbounded framework drift check and continuing remaining doctor checks"
+  fi
+else
+  warn "Framework drift checker is absent from the shipped tools tree"
+fi
+
 # Canonical Mosaic checks
 expect_file "$MOSAIC_HOME/STANDARDS.md"
 expect_file "$MOSAIC_HOME/USER.md"