Adopt @lavamoat/allow-scripts to gate npm install scripts

Disables dependency lifecycle scripts by default via .npmrc
(ignore-scripts=true) so arbitrary packages cannot execute code at
install time. An explicit allowlist in web/package.json opts specific
packages back in, and CI/Docker/Taskfile now run allow-scripts after
npm install to apply it.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Taskfile.yml

@@ -15,7 +15,9 @@ tasks:
   web:install:
     desc: Install frontend dependencies
     dir: "{{.WEB_DIR}}"
-    cmd: npm install
+    cmds:
+      - npm install
+      - npm exec -- allow-scripts
     sources:
       - package.json
     generates: