Restructure REV/ to use proper Claude Code subagent format:

- Create .claude/agents/ directory with 15 specialized agents
- Each agent has proper YAML frontmatter (name, description, model, tools)
- Each agent has veteran Postgres hacker role definition
- Critical agents (pg-review, pg-readiness, pg-hackers-letter, pg-feedback)
  use opus model for higher quality output

Agents by category:

Development & Build:
- pg-build: Build PostgreSQL with various configurations
- pg-test: Regression and TAP testing
- pg-benchmark: Performance testing with pgbench
- pg-debug: GDB debugging and core dump analysis

Code Quality:
- pg-style: pgindent and coding conventions
- pg-review: AI-assisted code review (opus)
- pg-coverage: Test coverage analysis
- pg-docs: DocBook SGML documentation

Patch Management:
- pg-patch-create: Create clean patches
- pg-patch-version: Manage versions and rebasing
- pg-patch-apply: Apply and test others' patches

Community Interaction:
- pg-hackers-letter: Write pgsql-hackers emails (opus)
- pg-commitfest: Navigate CommitFest workflow
- pg-feedback: Address reviewer feedback (opus)

Quality Gate:
- pg-readiness: Comprehensive submission checklist (opus)

Updated CLAUDE.md to serve as index referencing the agents.

Prefer 'Postgres' over 'PostgreSQL' throughout all agent files
and CLAUDE.md for consistency.

In the AI era, drafting code is fast. A working prototype speaks
louder than abstract discussion. Updated lifecycle and pitfalls
to reflect this new approach.

AI can assist with architectural fit evaluation and help craft
reasoning for building consensus through better email communication.

Subagents are invoked via natural language like:
  'Use the pg-review subagent to check my patch'
Not via @ prefix syntax.

- /pg-ready: Check patch readiness for submission
- /pg-submit: Prepare patch and draft email
- /pg-respond: Help respond to reviewer feedback

Slash commands provide quick access to common actions.