Modernize tiny-php for current PHP and Laravel workflows

[Copilot]

This updates tiny-php from a PHP 5.x / Travis-era package to a current PHP library with modern Composer, CI, and safer runtime behavior. The core encoding API stays intact, while package wiring, validation, and legacy integration paths are brought up to date.

• Package + toolchain

  • Raise the PHP baseline to ^8.1
  • Move Composer autoloading to PSR-4, including explicit support for the Laravel 5 namespace
  • Replace Travis config with a GitHub Actions CI workflow
  • Refresh package metadata, scripts, and CLI bin registration

• Core library hardening

  • Add strict types and typed APIs across the core classes
  • Validate Tiny alphabets up front and introduce a dedicated InvalidCharacterSet exception
  • Preserve existing negative-value normalization while rejecting malformed and out-of-range numeric strings
  • Detect decode overflow instead of silently returning invalid integers
  • Switch alphabet generation to a cryptographically secure shuffle

• Key generation + config handling

  • Modernize the tiny:generate commands
  • Add shared env-file update logic with correct precedence for TINY_KEY vs LEAGUE_TINY_KEY
  • Preserve literal key contents when writing .env
  • Keep legacy Laravel config files in sync where applicable
  • Update in-memory config via the config repository so generated keys are immediately visible in-process

• Laravel integration

  • Refresh both service providers with typed registration logic
  • Use console-only publish / command registration paths
  • Merge package config from the correct package location
  • Support both current and legacy env key names during resolution

• Docs + tests

  • Rewrite the README around current installation, usage, and upgrade expectations
  • Clarify Laravel setup for newer vs older integration paths
  • Expand test coverage for validation, env updates, numeric-string compatibility, overflow, and edge cases

use ZackKitzmiller\Tiny;

$tiny = new Tiny(Tiny::generateSet());

$encoded = $tiny->to(12345);
$decoded = $tiny->from($encoded);