fix: cleanup deps, fix bugs, restore CustomRequest & voucher charge

[knofte]

Summary

A combined housekeeping + bug fix PR addressing several open issues and long-standing problems:

1. Remove unused production dependencies

• Removed from dependencies: axios, q, bluebird, chai-as-promised-also-chain
• Moved to devDependencies: eslint-config-prettier, bluebird
• The codebase already uses native fetch — axios was only referenced in commented-out code
• Removes var q = require('q') from rave.base.js (imported but never used)
• Fixes flutterwave cloudflare error because of use of axios #168 — removing axios resolves Cloudflare Workers XMLHttpRequest incompatibility

2. Fix repository URLs in package.json

• URLs pointed to Flutterwave-node-v3 (old repo name) instead of Node-v3
• Affects npm page links for repository, issues, and homepage

3. Bump node-forge from 1.3.2 to ^1.3.3

• Security fix (CVE-2024-26458 — prototype pollution in ASN.1 parsing)
• node-forge is used for 3DES-ECB encryption of card payment data

4. Remove .DS_Store from repo, add to .gitignore

5. Restore CustomRequest feature (fixes #117)

• rave.custom.js and services/rave.custom.request.js were entirely commented out
• Rewritten using the modern async/await + _rave.request() pattern (no q/morx dependencies)
• Usage: flw.CustomRequest.custom('/v3/some-endpoint', data)

6. Restore voucher charge service

• services/charge/rave.voucher.js was entirely commented out, but lib/rave.charge.js still required and exported it
• Calling flw.Charge.voucher(data) threw TypeError: voucher_charge is not a function
• Rewritten using the modern pattern matching other charge services (ussd, ach, etc.)

7. Fix operator precedence bug in rave.base.js

// BEFORE (broken):
var requestMethod = RaveUtils.initDefaultValue(payload.method, 'POST' || 'PUT');
//                                              'POST' || 'PUT' always evaluates to 'POST'

var datakey = requestMethod == 'POST' || 'PUT' ? 'body' : 'qs';
//            (requestMethod == 'POST') || 'PUT' is always truthy

// AFTER (fixed):
var requestMethod = RaveUtils.initDefaultValue(payload.method, 'POST');
var datakey = (requestMethod === 'POST' || requestMethod === 'PUT') ? 'body' : 'qs';

8. Fix broken anchor link in documentation/transactions.md

• "Verify transaction with reference" linked to #verify-transaction instead of #verify-transaction-with-reference

Test plan

• Verify npm install works with reduced dependency set
• Verify existing charge services (card, ussd, bank_transfer) still work
• Test flw.Charge.voucher(data) with voucher payment data
• Test flw.CustomRequest.custom(path, data) with a valid API path
• Verify in Cloudflare Workers environment (no more XMLHttpRequest error)

[knofte]

@corneliusyaovi for your checks - let me know if you need help with anything else in this SDK.