feat: add base44 validate command for resource config files

[base44-os-gremlins]

Summary

• Adds a new base44 validate command that discovers all resource config files in the project's base44/ folder and validates each against its Zod schema
• Granular error collection: checks all files before exiting (no fail-fast), printing per-file pass/fail with field-level error details
• CI-safe: exits with code 1 when any validation errors are found, 0 on success
• No auth required: works without being logged in, useful for pre-push checks
• Validates all four resource types: entities, functions, agents, connectors

Example output

✓ base44/config.jsonc
✓ base44/entities/customer.jsonc
✗ base44/functions/send-email/function.jsonc
  Function name cannot be empty
    → at name
✓ base44/agents/support.jsonc

2 files checked — 1 passed, 1 failed

Test plan

• 9 integration tests added covering all resource types and edge cases
• bun run typecheck passes
• bun run lint passes (no new errors)
• All 9 tests pass locally

Relates to

Goal #870: https://github.com/base44-dev/gremlins/issues/870

🤖 Generated with Claude Code

[github-actions]

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npm i @base44-preview/cli@0.0.44-pr.411.fe4049c

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Or add it to your package.json dependencies:

{
  "dependencies": {
    "base44": "npm:@base44-preview/cli@0.0.44-pr.411.fe4049c"
  }
}

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