feat: tailwindClassOrder — priority-based class bucketing

[zipper]

Summary

• Adds tailwindClassOrder option — configurable class ordering through buckets (unknown / tailwind / regex patterns).
• Priority-based matching: explicit {pattern} buckets always win over "unknown" / "tailwind" catchalls, regardless of position. Config bucket order controls only where each group appears in the output.
• Also contains two n:class parser fixes discovered while testing on a real Latte project.

Config shape

Value is a string — path to JS/JSON file, or JSON-encoded array. Direct inline array in .prettierrc doesn't work because Prettier CLI collapses non-array:true option arrays to their last element.

// tailwind-class-order.js
module.exports = [
  [
    'unknown',
    { pattern: '^icon(?:--|$)' },
    'tailwind',
    { pattern: '^ajax' },
    { pattern: '^js-' }
  ],
  { unspecified: 'top' }
]

When the option is unset, behaviour is equivalent to the implicit default [["unknown", "tailwind"], {"unspecified":"top"}] — same output as before.

Use cases

• JS hooks at the end: { pattern: '^js-' } as last bucket
• BEM grouped with base: { pattern: '^icon(?:--|$)' }
• Component-like utilities up front: { pattern: '^h[1-6]$' }
• Custom class frameworks kept separate from generic Tailwind utilities

Breaking changes (relative to unreleased state of the feature)

• Option value is string-only. Inline arrays in .prettierrc are not supported — use an external .js/.json file or a JSON-encoded string. (API callers passing arrays to prettier.format still work.)

Commits

1. refactor — extract compareTailwindEntries shared by sortClassList and sortGroup
2. feat — new src/class-order.ts (types, parser, resolver, applyBuckets)
3. feat — wire tailwindClassOrder through options / types / loader / sort pipeline
4. test — integration tests for bucket algorithm + property-order interaction + BEM + n:class parity
5. docs — README + docs/options.md
6. feat! — priority-based matching, drop exception parameter (string-only config)
7. fix — don't split conditional branches that contain PHP concatenation ('foo bar' . $x->m() used to be shredded into tokens and corrupted)
8. fix — preserve newlines between sortable tokens in normalize-barriers mode (previously collapsed multi-line n:class layout to a single line)

Test plan

• Unit tests for parser / resolver / applyBuckets
• Integration tests — priority matching, BEM, greedy-style pattern stealing, unspecified placement, n:class parity, property-order interaction
• Full suite: 349/349 passed
• Lint clean (--max-warnings=0), build OK (CJS + ESM + DTS)
• Verified on a real project (fokus-optik) — JSON and JS config, priority-based matching with ^ajax / ^js- / ^icon(?:--|$) / ^h[1-6]$, default context preserves legacy behaviour
• Regression tests for both n:class fixes