fix: resolve critical issues in install.sh, settings.json, and worker-protocol

- install.sh: replace unreachable $? check with `if !` pattern (set -e
  exits before the check runs on Windows mklink failure)
- settings.json: remove fragile Bash deny patterns that can't match across
  path separators; broaden .env denies to recursive **/.env with Read/Write/Edit
- worker-protocol: align QA instruction with qa-checklist — qa_check goes in
  frontmatter envelope, not as a prose line

settings.json

@@ -19,18 +19,18 @@
       "Read(~/.ssh/**)",
       "Read(~/.aws/**)",
       "Read(~/.gnupg/**)",
-      "Read(./.env)",
-      "Read(./.env.*)",
+      "Read(**/.env)",
+      "Read(**/.env.*)",
       "Write(~/.ssh/**)",
       "Write(~/.aws/**)",
       "Write(~/.gnupg/**)",
+      "Write(**/.env)",
+      "Write(**/.env.*)",
       "Edit(~/.ssh/**)",
       "Edit(~/.aws/**)",
       "Edit(~/.gnupg/**)",
-      "Bash(*.ssh/*)",
-      "Bash(*.aws/*)",
-      "Bash(*.gnupg/*)",
-      "Bash(*.env*)"
+      "Edit(**/.env)",
+      "Edit(**/.env.*)"
     ],
     "ask": [
       "Bash(rm *)",