Build project metadata completeness validator

Create a TypeScript function that scores a climate tech project entry for metadata quality.

validateProjectMetadata(project: RawProject): ValidationResult

// RawProject: { name?: string, description?: string, repo_url?: string, category?: string, license?: string, [key: string]: unknown }
// ValidationResult: { valid: boolean, score: number, missing: string[], warnings: string[] }

Scoring rules (100 points max):

• name present and non-empty: +20
• description present and length > 50 chars: +20
• repo_url present and matches https://github.com/*: +20
• category is from the allowed list (export a VALID_CATEGORIES constant): +20
• license is a recognized SPDX identifier (MIT, Apache-2.0, GPL-3.0, AGPL-3.0, BSD-2-Clause, BSD-3-Clause, MPL-2.0): +20

Warnings (reduce score by 10 each, floor at 0):

• Description is present but under 50 chars
• repo_url is present but not a GitHub URL
• License is present but not in the SPDX list

valid is true if score >= 60.

Write unit tests for: a perfect entry, a partial entry missing 2 fields, an entry with warnings only, and an empty object.