fix: clean up command templates (specify, analyze) (#1810)

* fix: clean up command templates (specify, analyze)

- specify.md: fix self-referential step number (step 6c → proceed to step 7)
- specify.md: remove empty "General Guidelines" heading before "Quick Guidelines"
- analyze.md: deduplicate {ARGS} — already present in "User Input" section at top

* fix: restore ## Context heading in analyze template

Address PR review feedback from @dhilipkumars: keep the ## Context
markdown heading to preserve structural hierarchy for LLM parsing.