feat: Major security toolkit expansion based on integration feedback

Based on real-world WordPress semantic theme integration, this commit
addresses gaps identified during testing with sanctify-php:

New Modules:
- TurtleEscaper: W3C-compliant RDF Turtle escaping (unique differentiator)
- Headers: Security headers (CSP, HSTS, X-Frame-Options, CORS, etc.)

Enhanced Validator:
- IP validation (v4, v6, combined)
- UUID, slug, JSON validation
- Security validators (noNullBytes, safeFilename, httpsUrl)
- Static methods (no instance required)

Enhanced Sanitizer:
- Context-aware escaping (HTML, JS, CSS, URL, JSON)
- Filename sanitization
- Static methods (no instance required)

Documentation:
- HANDOVER_SANCTIFY.md: Integration guidance for sanctify-php team
- ROADMAP_PRIORITY.md: Prioritized roadmap based on real-world usage
- Updated README with new API reference and examples

Compliance:
- SPDX license headers on all PHP files
- All classes marked final for security

Author: claude

HANDOVER_SANCTIFY.md

@@ -0,0 +1,244 @@
+# Handover Document: sanctify-php Integration Insights
+
+## Context
+
+This document summarizes findings from integrating `php-aegis` and `sanctify-php` into a WordPress semantic theme (wp-sinople-theme). It provides actionable recommendations for the `sanctify-php` team based on real-world usage patterns.
+
+## Role Clarification
+
+| Tool | Role | When Used |
+|------|------|-----------|
+| **php-aegis** | Runtime security library | During request handling (validation, sanitization, headers) |
+| **sanctify-php** | Static analysis tool | During development/CI (find vulnerabilities before deploy) |
+
+These are **complementary**, not competing tools:
+- `sanctify-php` finds the bugs
+- `php-aegis` provides the fixes
+
+## Issues Discovered During Integration
+
+### 1. Haskell Toolchain Dependency
+
+**Problem**: `sanctify-php` requires GHC/Cabal to build, which is a significant barrier for PHP developers.
+
+**Impact**: Most PHP teams don't have Haskell expertise or toolchain installed.
+
+**Recommendations**:
+- Provide pre-built binaries for Linux (x86_64, aarch64), macOS (Intel, Apple Silicon), Windows
+- Create official Docker image: `ghcr.io/hyperpolymath/sanctify-php:latest`
+- Consider GitHub Actions integration that runs analysis without local install
+- Add installation via common package managers (Homebrew, apt, nix)
+
+**Example Docker usage**:
+```bash
+docker run --rm -v $(pwd):/workspace ghcr.io/hyperpolymath/sanctify-php analyze /workspace
+```
+
+### 2. PHP 8.x Syntax Support
+
+**Problem**: Parser may not handle all PHP 8.x syntax (enums, union types, named arguments, attributes, match expressions, constructor property promotion).
+
+**Test cases needed**:
+```php
+// Enums (PHP 8.1+)
+enum Status: string {
+    case Draft = 'draft';
+    case Published = 'published';
+}
+
+// Union types (PHP 8.0+)
+function process(string|int $input): string|false { ... }
+
+// Attributes (PHP 8.0+)
+#[Route('/api/users')]
+class UserController { ... }
+
+// Constructor property promotion (PHP 8.0+)
+class User {
+    public function __construct(
+        public readonly string $name,
+        private int $age = 0,
+    ) {}
+}
+
+// Named arguments (PHP 8.0+)
+htmlspecialchars(string: $input, flags: ENT_QUOTES);
+
+// Match expressions (PHP 8.0+)
+$result = match($status) {
+    Status::Draft => 'Editing',
+    Status::Published => 'Live',
+};
+```
+
+**Recommendation**: Add PHP 8.x grammar rules and comprehensive test suite.
+
+### 3. RDF/Turtle Output Context Awareness
+
+**Problem**: Static analyzer doesn't detect RDF/Turtle injection vulnerabilities in semantic web themes.
+
+**Background**: Semantic WordPress themes output RDF Turtle format for linked data. Standard XSS detection won't catch Turtle-specific injection vectors.
+
+**Vulnerable pattern** (not currently detected):
+```php
+// DANGEROUS: addslashes() is insufficient for Turtle
+$turtle = '<' . $uri . '> rdfs:label "' . addslashes($label) . '" .';
+```
+
+**Attack vectors**:
+```turtle
+# Turtle escape sequences
+\n \r \t \\ \" \uXXXX \UXXXXXXXX
+
+# IRI injection
+<http://evil.com> owl:sameAs <http://trusted.com>
+```
+
+**Recommendation**: Add detection rules for:
+- `addslashes()` used in RDF/Turtle context
+- Unescaped variables in Turtle string literals (`"..."`)
+- Unescaped IRIs (`<...>`)
+- Missing use of proper escaping functions
+
+**Suggested rule signatures**:
+```
+turtle_string_injection: Detects unescaped user input in Turtle string literals
+turtle_iri_injection: Detects unescaped user input in Turtle IRIs
+rdf_semantic_injection: Detects potential semantic attacks via RDF
+```
+
+### 4. WordPress Integration Documentation
+
+**Problem**: No clear guidance for WordPress-specific vulnerability patterns.
+
+**WordPress-specific patterns to detect**:
+
+```php
+// DANGEROUS: Direct $_GET/$_POST usage
+echo $_GET['query'];  // XSS
+
+// DANGEROUS: Missing nonce verification
+if (isset($_POST['action'])) { ... }  // CSRF
+
+// DANGEROUS: Direct SQL interpolation
+$wpdb->query("SELECT * FROM users WHERE id = " . $_GET['id']);  // SQLi
+
+// DANGEROUS: Unescaped output
+echo $user_input;  // Should use esc_html(), esc_attr(), etc.
+
+// DANGEROUS: Privileged action without capability check
+add_action('wp_ajax_delete_user', 'delete_user_handler');
+function delete_user_handler() {
+    // Missing: current_user_can('delete_users')
+    wp_delete_user($_POST['user_id']);
+}
+```
+
+**WordPress-specific safe patterns**:
+```php
+// Safe escaping functions
+esc_html($text)
+esc_attr($attr)
+esc_url($url)
+wp_kses($html, $allowed)
+wp_kses_post($html)
+
+// Safe nonce verification
+wp_verify_nonce($_POST['_wpnonce'], 'action_name')
+check_admin_referer('action_name')
+
+// Safe capability checks
+current_user_can('edit_posts')
+```
+
+**Recommendation**: Create WordPress-specific ruleset that:
+- Detects missing `esc_*` function usage
+- Detects missing nonce verification in form handlers
+- Detects missing capability checks in AJAX handlers
+- Recognizes WordPress sanitization functions as safe sinks
+
+### 5. IndieWeb/Micropub Pattern Detection
+
+**Problem**: No awareness of IndieWeb protocols (Micropub, IndieAuth, Webmention).
+
+**Patterns to detect**:
+
+```php
+// DANGEROUS: Missing IndieAuth token verification
+function handle_micropub($request) {
+    $content = $request['content'];  // Unverified!
+    create_post($content);
+}
+
+// DANGEROUS: Webmention SSRF
+function verify_webmention($source) {
+    $response = wp_remote_get($source);  // Can hit internal IPs
+}
+
+// DANGEROUS: Micropub content injection
+$mf2 = Mf2\parse($html, $source);
+$content = $mf2['items'][0]['properties']['content'][0];
+echo $content;  // Unsanitized from external source
+```
+
+**Recommendation**: Add rules for common IndieWeb vulnerability patterns.
+
+## Integration Architecture
+
+```
+┌─────────────────────────────────────────────────────────────┐
+│                    Development Workflow                      │
+├─────────────────────────────────────────────────────────────┤
+│                                                              │
+│  ┌──────────────┐    ┌──────────────┐    ┌──────────────┐  │
+│  │  Developer   │───▶│ sanctify-php │───▶│   Fix Code   │  │
+│  │  Writes Code │    │  (Analysis)  │    │  (Guidance)  │  │
+│  └──────────────┘    └──────────────┘    └──────────────┘  │
+│                              │                               │
+│                              ▼                               │
+│                     ┌──────────────┐                        │
+│                     │  php-aegis   │                        │
+│                     │  (Runtime)   │                        │
+│                     └──────────────┘                        │
+│                                                              │
+└─────────────────────────────────────────────────────────────┘
+```
+
+## Recommended sanctify-php Output Format
+
+When `sanctify-php` detects a vulnerability, it should suggest the `php-aegis` fix:
+
+```
+VULNERABILITY: XSS in output context
+FILE: theme/template.php:42
+CODE: echo $user_input;
+
+RECOMMENDATION:
+  Use php-aegis Sanitizer for proper encoding:
+
+  Before: echo $user_input;
+  After:  echo \PhpAegis\Sanitizer::html($user_input);
+
+  Install: composer require hyperpolymath/php-aegis
+```
+
+## Priority Recommendations Summary
+
+| Priority | Issue | Effort |
+|----------|-------|--------|
+| P0 | Pre-built binaries / Docker image | Medium |
+| P0 | PHP 8.x syntax support | High |
+| P1 | WordPress-specific rulesets | Medium |
+| P1 | RDF/Turtle context detection | Medium |
+| P2 | IndieWeb protocol patterns | Low |
+| P2 | php-aegis fix suggestions in output | Low |
+
+## Contact
+
+For questions about this integration or to coordinate between repos:
+- php-aegis: https://github.com/hyperpolymath/php-aegis
+- Integration tested in: wp-sinople-theme
+
+---
+
+*Generated from real-world WordPress semantic theme integration experience.*