fix: replace zsh-incompatible raw globs with find-based alternatives and setopt guards

Zsh's NOMATCH option (on by default) causes raw globs like `*.yaml` and
`*deploy*` to throw errors when no files match, instead of silently expanding
to nothing as bash does. The preamble resolver already handled this correctly
with find, but 38 glob instances across 13 templates and 2 resolvers still
used raw shell globs.

Two fix approaches based on complexity:
- find-based replacement for cat/for/ls-with-pipes patterns (.github/workflows/)
- setopt +o nomatch guard for simple ls -t patterns (~/.gstack/, ~/.claude/)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

qa/SKILL.md.tmpl

@@ -96,6 +96,7 @@ Before falling back to git diff heuristics, check for richer test plan sources:
 
 1. **Project-scoped test plans:** Check `~/.gstack/projects/` for recent `*-test-plan-*.md` files for this repo
    ```bash
+   setopt +o nomatch 2>/dev/null || true  # zsh compat
    {{SLUG_EVAL}}
    ls -t ~/.gstack/projects/$SLUG/*-test-plan-*.md 2>/dev/null | head -1
    ```