Centralize Ashby slug list to eliminate duplication between Python and TypeScript

[Copilot]

The curated Ashby company slug list was duplicated between scripts/ashby_slugs_verified.py and backend/src/services/theirstack-fetcher.ts, creating drift risk.

Changes

• Created canonical source: backend/src/constants/ashby-slugs.json containing all 251 company slugs
• Python script: Removed hardcoded array, now loads from JSON via load_canonical_slugs()
• TypeScript backend: Replaced 34-line hardcoded array with runtime JSON import using readFileSync
• Gitignore: Excluded generated script outputs (.txt, .csv files)

Implementation

TypeScript loads the shared list at module initialization:

const __filename = fileURLToPath(import.meta.url);
const __dirname = dirname(__filename);
const ashbySlugsPath = join(__dirname, '../constants/ashby-slugs.json');
const ASHBY_COMPANY_SLUGS: readonly string[] = JSON.parse(readFileSync(ashbySlugsPath, 'utf-8'));

Python script dynamically loads the same source:

def load_canonical_slugs() -> list[str]:
    canonical_path = Path(__file__).resolve().parent.parent / 'backend' / 'src' / 'constants' / 'ashby-slugs.json'
    with canonical_path.open('r') as f:
        return json.load(f)

Both systems now reference a single source of truth, eliminating maintenance overhead and drift.

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