feat: Add dual PSR-7 version support and related documentation

[code-cfernandes]

• Introduced compatibility for both PSR-7 v1.x and v2.x in PivotPHP.
• Added scripts for switching between PSR-7 versions and checking the current version.
• Updated composer.json to enforce PSR-7 v2.0 as the default while allowing v1.x.
• Enhanced README.md with instructions for version switching and compatibility details.
• Created detailed implementation summary and PSR-7 compatibility status documentation.
• Implemented Psr7VersionDetector for automatic version detection.
• Added Psr7V1CompatibilityTrait for PHPDoc annotations to support v1.x.
• Refactored HTTP components to maintain compliance with both PSR-7 versions.
• Improved testing and validation scripts for both PSR-7 versions.

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🔗 Issues Relacionadas

Fixes #7

[Copilot]

Pull Request Overview

This PR adds support for both PSR-7 v1.x and v2.x in PivotPHP by introducing automatic detection, version-switching scripts, updated composer constraints, PHPDoc compatibility traits, and extensive documentation updates.

• Implemented a Psr7VersionDetector for runtime PSR-7 version detection.
• Added scripts (switch-psr7-version.php, adapt-psr7-v1.php) to toggle return-type signatures and update composer requirements.
• Updated documentation (docs/technical/*) and composer.json for dual PSR-7 compatibility.

Reviewed Changes

Copilot reviewed 20 out of 20 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
src/Http/Psr7/* (multiple)	Removed/added return types on PSR-7 methods for v1/v2 compatibility
src/Http/Psr7/Factory/Psr7VersionDetector.php	Added version detection logic
src/Http/Psr7/Psr7V1CompatibilityTrait.php	Introduced PHPDoc stubs for v1.x
scripts/switch-psr7-version.php	Script to switch between PSR-7 versions
scripts/adapt-psr7-v1.php	Script to strip return types for v1.x
composer.json	Adjusted PSR-7 requirement
docs/technical/http/README.md	Expanded HTTP component docs with PSR-7 dual-support section
docs/technical/compatibility/psr7-*.md	New compatibility guides

Comments suppressed due to low confidence (5)

README.md:150

• The README mentions a --check flag, but the switch script only accepts 1 or 2; update the documentation or implement support for --check in the script to avoid confusion.

php scripts/switch-psr7-version.php --check

docs/technical/http/README.md:125

• The example references withHeaderStrict, which is not defined in the PSR-7 implementation; either remove this call or provide its implementation details.

   $response = $response->withHeaderStrict('X-Custom', $value);

src/Http/Psr7/Uri.php:66

• [nitpick] When targeting PSR-7 v1.x (no native return types), consider adding @return string to the docblock of getScheme() (and similar methods) to maintain IDE and static analysis support.

    public function getScheme()

src/Http/Psr7/Factory/Psr7VersionDetector.php:22

• Add unit tests for Psr7VersionDetector::getVersion(), isV1(), and isV2() to validate correct detection across environments and to ensure the version cache reset works as expected.

    public static function getVersion(): string

composer.json:42

• The composer constraint now only allows PSR-7 v1.x; to match the PR description and support both versions (or default to v2.x), restore the constraint to "^1.1|^2.0" or set a default of "^2.0" while allowing "^1.1".

        "psr/http-message": "^1.1",