feat: add sql subcommand for creating neon projects

[devin-ai-integration]

Add new SQL subcommand to neonctl that enables defining Neon databases using SQL-like syntax.

Features:

• SQL-style syntax for project creation
• Support for all Neon API project creation functionality
• Configuration via YAML-like specification block
• Comprehensive test coverage

Example usage:

CREATE MANAGED SERVICE mydb TYPE=POSTGRES_NEON SPECIFICATION=7573
spec:
  maxVCpu: 8
  postgresVersion: 17
  autoSuspend: True
  historyRetentionSeconds: 0
  setupSQL = setupSQL.sql
7573

Link to Devin run: https://app.devin.ai/sessions/a50c7ceac2054960bee7ef19f190eea3

[devin-ai-integration]

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[devin-ai-integration]

The CI build is failing because the workflow is using bun install --frozen-lockfile while the project is configured to use pnpm (as specified in package.json's packageManager field).

There seems to be a mismatch between the CI configuration and the project's package manager setup. Should we:

1. Update the CI workflow to use pnpm instead of bun (preferred since package.json specifies pnpm), or
2. Switch the project to use bun consistently?

Please advise on the preferred approach.