v1.5.4

Changelog

• 130ec88 Apply suggestions from code review
• 41e5ce7 Bump version: 1.5.3 → 1.5.4
• 91831b4 Merge origin/main and complete stale exit contract
• 7c4ae4a build: make release verification artifact-specific
• d68cc06 cli: make stale command return strict exit codes
• 4d85f35 cli: make stale command return strict exit codes (#26)
• 13b6949 feat: persist MCP refresh artifacts and align CLI/MCP contracts
• 971ca3c security: confine repository filesystem access