CI: run timeout inside sudo, per apt command, so the kill reaches apt-get

Addresses Copilot review on QuantEcon/lecture-intro.zh-cn#301: with timeout wrapping sudo, a timed-out attempt terminated sudo and the bash -c shell but could orphan apt-get holding the dpkg lock, making the retry block instead of retry. timeout is now the direct parent of each apt-get (inside sudo, -k 30s escalation): update 1m/2m, install 3m/12m for graphviz/texlive. Step budgets unchanged.

Author: mmcky

.github/workflows/ci.yml

@@ -28,11 +28,12 @@ jobs:
       - name: Install latex dependencies
         timeout-minutes: 30
         run: |
-          # Retried with a per-attempt timeout: a stalled Ubuntu mirror otherwise
+          # Retried with per-command timeouts (timeout inside sudo, so the kill reaches
+          # apt-get and the dpkg lock is released): a stalled Ubuntu mirror otherwise
           # hangs this step for hours (two 358-minute hangs on 2026-08-18).
           pkgs="texlive-latex-recommended texlive-latex-extra texlive-fonts-recommended texlive-fonts-extra texlive-xetex latexmk xindy dvipng cm-super"
           for attempt in 1 2; do
-            timeout 14m sudo bash -c "apt-get -qq update && apt-get install -y $pkgs" && break
+            sudo timeout -k 30s 2m apt-get -qq update && sudo timeout -k 30s 12m apt-get install -y $pkgs && break
             if [ "$attempt" = 2 ]; then echo "apt-get failed after 2 attempts"; exit 1; fi
             echo "apt-get attempt $attempt failed; retrying in 30s"; sleep 30
           done

.github/workflows/publish.yml

@@ -33,11 +33,12 @@ jobs:
       - name: Install latex dependencies
         timeout-minutes: 30
         run: |
-          # Retried with a per-attempt timeout: a stalled Ubuntu mirror otherwise
+          # Retried with per-command timeouts (timeout inside sudo, so the kill reaches
+          # apt-get and the dpkg lock is released): a stalled Ubuntu mirror otherwise
           # hangs this step for hours (two 358-minute hangs on 2026-08-18).
           pkgs="texlive-latex-recommended texlive-latex-extra texlive-fonts-recommended texlive-fonts-extra texlive-xetex latexmk xindy dvipng cm-super"
           for attempt in 1 2; do
-            timeout 14m sudo bash -c "apt-get -qq update && apt-get install -y $pkgs" && break
+            sudo timeout -k 30s 2m apt-get -qq update && sudo timeout -k 30s 12m apt-get install -y $pkgs && break
             if [ "$attempt" = 2 ]; then echo "apt-get failed after 2 attempts"; exit 1; fi
             echo "apt-get attempt $attempt failed; retrying in 30s"; sleep 30
           done