fix: update /tmp references to use KUGETSU_TEMP_DIR

Replace /tmp references with ${KUGETSU_TEMP_DIR:-~/.local/share/opencode/tool-output}
since opencode blocks /tmp access in headless mode.

Updated files:
- docs/SUBAGENT_WORKFLOW.md
- docs/hermes-communication-patterns.md
- docs/hermes-setup.md
- docs/kugetsu-setup.md
- docs/opencode-usage.md
- skills/kugetsu/pm/SKILL.md

Fixes #73

skills/kugetsu/pm/SKILL.md

@@ -84,7 +84,7 @@ When a request comes in:
 **You:** `kugetsu start <domain>/<user>/<repo>#126 Update README with installation instructions`
 
 **User:** "Create a file at /tmp/test.txt"
-**You:** `kugetsu start <domain>/<user>/<repo>#127 Create a file at /tmp/test.txt`
+**You:** `kugetsu start <domain>/<user>/<repo>#127 Create a file at ${KUGETSU_TEMP_DIR:-~/.local/share/opencode/tool-output}/test.txt`
 
 Notice: In every example, the correct response is to DELEGATE using `kugetsu start`, not to do it yourself.