feat(php): add native PHP implementation and composer package

[konard]

Closes #284

Adds a native PHP implementation of Links Notation and prepares the
link-foundation/links-notation package for Composer/Packagist, following the
structure of the existing JavaScript, Python, Rust, Go, Java and C# ports.

What is added

• php/src/ — native port of the parser and formatter:
  • Parser — full lino parser (inline links, parenthesized groups, significant
    indentation, indented-id syntax, multi-quote strings, multiline quoted
    references, nested indentation contexts inside parentheses per Indentation is structural at the root but ignored inside ( ), so parenthesised groups cannot express nested records #282), with
    input size and depth limits
  • Link — link data structure (format, equals, simplify, combine,
    escapeReference, …)
  • Formatter — document formatting
  • FormatConfig — formatting options (line length, inline ref count,
    grouping, indent string, prefer-inline)
  • ParseException — parse error type
• php/composer.json — Composer package link-foundation/links-notation
  (PSR-4 LinkFoundation\LinksNotation\, PHP >= 8.1, ext-mbstring,
  Unlicense, version 0.1.0) with test, lint and lint:fix scripts
• php/tests/ — PHPUnit suite ported 1:1 from the Python test suite
• .github/workflows/php.yml — lint (PSR-12 via PHP_CodeSniffer), test matrix
  on PHP 8.1/8.2/8.3/8.4, Packagist publish (skipped when the version is
  already published or when the Packagist secrets are absent) and GitHub
  release with the repo-standard php_<version> tag
• php/README.md, php/README.ru.md, PHP entries in the root README.md /
  README.ru.md, and a CHANGELOG.md note
• examples/php/quick_start.php — runnable version of every README snippet

How to reproduce / verify

cd php
composer install
composer run-script test   # PHPUnit
composer run-script lint   # PSR-12
php ../examples/php/quick_start.php

Automated tests

The PHP suite is a direct port of the Python one, so behaviour parity is
checked rather than assumed: single-line parsing, nested parsing, multiline
documents, multi-quote strings, multiline quoted strings, edge cases, nested
indentation (#282), nested self-references, indented-id syntax, indentation
consistency, mixed indentation modes, Link/FormatConfig unit tests and API
tests.

Local run: OK (173 tests, 469 assertions), phpcs clean.

Packagist note

Repository release tags use the php_<version> format, which Packagist cannot
parse as a version, so composer.json keeps an explicit version field and CI
validates with composer validate --strict --no-check-version. Publishing
requires the PACKAGIST_USERNAME and PACKAGIST_TOKEN repository secrets; the
publish step is skipped with a message when they are not configured.

[konard]

Working session summary

The PHP port is complete and PR #285 is ready for review: #285

What landed (3 commits on issue-284-ed60ce81c8a6, 32 files, +4270 lines, nothing removed):

• php/src/ — native Parser, Link, Formatter, FormatConfig, ParseException (namespace LinkFoundation\LinksNotation), covering inline links, parenthesized groups, significant indentation, indented-id syntax, multi-quote strings, multiline quoted references, and the nested-parenthesis indentation semantics from Indentation is structural at the root but ignored inside ( ), so parenthesised groups cannot express nested records #282, with input-size/depth limits.
• php/composer.json — Composer package link-foundation/links-notation, PSR-4, PHP ≥ 8.1 + ext-mbstring, Unlicense, version 0.1.0, with test/lint/lint:fix scripts.
• php/tests/ — 15 PHPUnit classes ported 1:1 from the Python suite. Local and CI: 173 tests, 469 assertions, all passing; phpcs (PSR-12) clean.
• .github/workflows/php.yml — same shape as the other language workflows: changed-file detection, lint, test matrix 8.1/8.2/8.3/8.4, Packagist publish (skipped when the version is already published or the secrets are missing), release tagged php_<version> titled [PHP] <version>.
• Docs: php/README.md, php/README.ru.md, PHP badge row + Quick Start in both root READMEs, CHANGELOG.md entry, and examples/php/quick_start.php — I ran that example and verified every documented snippet's output rather than asserting it.

CI on the pushed head e02e848: findChangedPhpFiles, lint, test (8.1–8.4) and check-bom-consistency all pass; publishToPackagist/publishRelease correctly skip on a PR branch. main was already merged (no divergence), working tree is clean, and there are no comments on the issue or PR to address.

One thing worth your decision: publishing to Packagist needs PACKAGIST_USERNAME and PACKAGIST_TOKEN repository secrets, which I cannot set. Until they exist the publish step exits 0 with a skip message. Also, because release tags here use the php_<version> format that Packagist cannot parse as a version, composer.json keeps an explicit version field and CI validates with composer validate --strict --no-check-version.

---

This summary was automatically extracted from the AI working session output.

[konard]

🤖 Solution Draft Log

This log file contains the complete execution trace of the AI solution draft process.

💰 Cost: $7.870472

📊 Context and tokens usage:

Claude Opus 5: (3 sub-sessions)

1. 114.9K / 1M (11%) input tokens, 30.3K / 128K (24%) output tokens
2. 111.8K / 1M (11%) input tokens, 39.5K / 128K (31%) output tokens
3. 51.0K / 1M (5%) input tokens, 4.8K / 128K (4%) output tokens

Total: (4.4K new + 236.5K cache writes + 6.4M cache reads) input tokens, 90.9K output tokens, $7.870472 cost

🤖 Models used:

• Tool: Anthropic Claude Code
• Requested: opus (claude-opus-5)
• Thinking level: medium (~15999 tokens)
• Model: Claude Opus 5 (claude-opus-5)

📎 Log file uploaded as Gist (2813KB)

• View complete solution draft log

---

Now working session is ended, feel free to review and add any feedback on the solution draft.

[konard]

✅ Ready to merge

This pull request is now ready to be merged:

• All CI checks have passed
• No merge conflicts
• No pending changes

---

Monitored by hive-mind with --auto-restart-until-mergeable flag