chore(agents): install mattpocock skills + per-repo agent config

- 38 skills from mattpocock/skills into .agents/skills/ (symlinked into
  .claude/skills/ for Claude Code)
- skills-lock.json for reproducible installs
- docs/agents/: issue-tracker (Gitea via tea CLI), triage-labels
  (default five-role vocabulary), domain docs (single-context)
- CLAUDE.md: add '## Agent skills' section pointing at docs/agents/
- .gitignore: un-ignore docs/agents/ under the local /docs/* rule

.agents/skills/git-guardrails-claude-code/scripts/block-dangerous-git.sh

@@ -0,0 +1,25 @@
+#!/bin/bash
+
+INPUT=$(cat)
+COMMAND=$(echo "$INPUT" | jq -r '.tool_input.command')
+
+DANGEROUS_PATTERNS=(
+  "git push"
+  "git reset --hard"
+  "git clean -fd"
+  "git clean -f"
+  "git branch -D"
+  "git checkout \."
+  "git restore \."
+  "push --force"
+  "reset --hard"
+)
+
+for pattern in "${DANGEROUS_PATTERNS[@]}"; do
+  if echo "$COMMAND" | grep -qE "$pattern"; then
+    echo "BLOCKED: '$COMMAND' matches dangerous pattern '$pattern'. The user has prevented you from doing this." >&2
+    exit 2
+  fi
+done
+
+exit 0