Feat/go modules migration

[fedir]

Complete modernization of ghstat for Go 1.26 + macOS M4, plus a major hybrid analysis feature that makes stats reliable for all repos including inactive ones.

Infrastructure

• Migrate from GOPATH to Go modules (go.mod / go.sum)
• Replace deprecated ioutil with io/os
• Replace Travis CI with GitHub Actions
• Add Makefile with all developer commands (build, test, vet, cache-clear, clone-clear, rate-limit, run-all, etc.)

Auth & configuration

• Switch GitHub auth from basic (GH_USR/GH_PASS) to Bearer token (GH_TOKEN)
• Auto-load .env on startup via godotenv
• Configurable HTTP timeout (GH_HTTP_TIMEOUT), stats retry count (GH_STATS_MAX_RETRIES) and interval (GH_STATS_RETRY_INTERVAL) via .env
• Lazy HTTP client init so .env values are respected

Hybrid analysis (main feature)

• Every repo is now analysed from two sources merged into one record: GitHub API (stars, forks, issues, license, author, tags) + local git clone (commits, additions/deletions, commit
  size, contribution period, returning contributors)
• On first run repos are cloned to tmp/projects/; on re-runs clones are updated (git fetch + reset --hard origin/HEAD)
• Solves the stats/contributors 202-forever problem for old/inactive repos — local git is always authoritative for commit history

UX

• -f output path is now required (no silent default)
• Per-repo progress logging with timing; overall [X/N] counter
• make cache-clear preserves clones; new make clone-clear target

Stats updated

• All 29 CSV files refreshed with hybrid data
• Framework lists modernized: Go (added fiber, beego new org), Rust (axum, Rocket, warp, leptos), JS (react/vue/angular/svelte/solid + express/fastify/nest/koa/hono +
  next/nuxt/remix/sveltekit/analog), PHP CMS (craftcms, statamic)

Tests

• Coverage: main package 87% → 94%, new localstat package 53%
• Added tests for ranking logic, CSV formatting, cache clearing, git stat functions, contributor math