docs(issues): add #1771 spec and enforce manual verification workflow

[josecelano]

Summary

This PR intentionally contains only issue/spec workflow documentation updates so they can be reviewed and merged before implementation starts.

What changed

• Added and opened issue spec #1771
• Updated EPIC Overhaul clients #669 to include the new pending sub-issue/spec
• Clarified spec-first PR workflow for complex issues
• Strengthened templates and create-issue skill to require:
  • automatic checks after implementation (linter all, relevant tests, pre-push where applicable)
  • manual verification scenarios with status and evidence tracking
  • post-implementation acceptance criteria review

Why

For complex issues, merging the issue spec first improves visibility and allows review of scope/acceptance criteria before code changes.

Manual verification was frequently omitted by agents; templates/skill now make it an explicit required step.

Scope of this PR

Documentation/spec process changes only. No production code changes.

[josecelano]

ACK 56e0b1a