docs: memory + usage docs for review-minimax and ci-triage-minimax offloads

Four memory docs (2 skills, 2 wrapper scripts) + MEMORY.md index lines;
ask-minimax-usage.md gains both delegation targets. Records the gac
v0.0.2.10 token-discovery gap (needs GITEA_TOKEN_FILE pointed at
ai_admin/token; the wrapper defaults it).

Claude-Session: https://claude.ai/code/session_01Ku87DDWwbJkTx6SuV3sQDc

claude/ask-minimax-usage.md

@@ -10,6 +10,8 @@
 - Format conversion of large files (CSV↔JSON, XML↔YAML, etc.)
 - Bulk find-and-extract across many files where only the matches matter
 - Broad read-only codebase exploration ("where does X live", "how is Y wired up") — use the specialised `/explore-minimax` skill, which enforces read-only, requires `file:line` citations, and falls back to the Explore agent on failure
+- First-pass code review of agent-produced branches — use the specialised `/review-minimax` skill (findings file, credential gates, adjudicated in-session; pre-filter before `/code-review`, never final authority)
+- CI failure triage of failed Gitea Actions runs — use the specialised `/ci-triage-minimax` skill (gac log fetch + redaction; failing step/cause file; canonical after `gac tail --until run-complete` exits 1)
 
 ## Skip it for