Consolidated config: unified kata.yaml, simplified setup, upstream merge

[codevibesmatter]

Summary

Replace the current batteries/setup system with a consolidated config surface and simpler setup flow.

Problem

• Config scattered across 10+ file categories (kata.yaml, interviews.yaml, subphase-patterns.yaml, verification-tools.md, templates, prompts, agents, etc.)
• Batteries concept is confusing — dual system (package vs project), 2-tier lookup, --update clobbers local changes
• Setup produces generic output regardless of project

Proposed changes

Unified kata.yaml:

• Absorb interviews.yaml → interviews: section
• Absorb subphase-patterns.yaml → subphase_patterns: section
• Absorb verification-tools.md → structured project.* fields
• Add per-mode rules: string[] for project-specific instructions
• Move planning/spec-templates/ → .kata/spec-templates/

Simplified setup:

• kata setup creates skeleton with seed files (templates, prompts, agents, spec-templates) copied from package
• No --batteries flag — setup does everything
• All files stamped with kata_version for upstream merge tracking

Upstream merge:

• kata update with version-tracked smart merge
• Structural changes (phases, dependencies) merge cleanly
• Behavioral changes (customized instructions) preserved
• Distinguishes upstream-owned vs project-customized content

Remove:

• batteries/ directory concept
• kata batteries command
• 2-tier template lookup
• 2-tier merge for interviews/subphase-patterns
• batteries-backup/ logic

Directory layout

.kata/
  kata.yaml              # unified config
  templates/             # mode templates (project-owned)
  prompts/               # review prompts
  spec-templates/        # spec scaffolds
  sessions/              # runtime state
.claude/
  agents/                # agent definitions (Claude convention)
  settings.json          # hooks

Research

See planning/research/2026-03-31-setup-overhaul-upstream-merging.md

[codevibesmatter]

Spec approved: planning/specs/35-consolidated-config.md

Ready for implementation: kata enter implementation --issue=35