Systematic: shell syntax in git.run() calls across 8+ tools

[TerminalGravity]

Problem

run() in lib/git.ts uses execFileSync('git', args) — no shell interpretation. But many tools pass strings containing shell operators that silently break:

• 2>/dev/null — passed as literal git args
• || fallback — not executed, literal args
• | tail -1 / | grep — literal args
• && git commit — literal args
• < file — literal args
• git diff ... — becomes git git diff ...

Already fixed

• clarify-intent (fix: clarify_intent non-git commands silently broken via git.run() #170)
• checkpoint, what-changed, session-health (fix: broken shell syntax in git.run() calls (checkpoint, what-changed, session-health) #171)

Still broken

Tool	Line(s)	Shell syntax used
verify-completion	37, 58, 83, 115, 133	cat, pipe, 2>/dev/null, npm run build via git
token-audit	42-43, 66, 83, 142	2>/dev/null, wc -l <, tail -c
session-handoff	11, 47	command -v, gh pr list ... || echo
audit-workspace	39, 78	2>/dev/null, find ... | wc -l
sharpen-followup	90	2>/dev/null
scope-work	131	git ls-files | head | grep
enrich-agent-task	32-56	2>/dev/null, head -30, grep pipes
sequence-tasks	93	2>/dev/null

Fix approach

For each tool:

1. Replace shell-piped commands with array-arg run() calls
2. Do filtering/piping in JS (split, filter, slice)
3. For non-git commands (wc, find, cat), use Node.js fs/child_process directly
4. Remove 2>/dev/null — run() already catches errors gracefully