Fix ContentEncoding and ContentMediaType to Draft-06

[Copilot]

contentEncoding and contentMediaType were incorrectly marked as Draft-07 features. These annotations were introduced in JSON Schema Draft-06.

Changes:

• Moved ContentMediaType and ContentEncoding enum cases to new "Draft 06 features" section in SchemaFeature.php
• Updated getMinimumVersion() to return SchemaVersion::Draft_06 for both features
• Fixed test expectations in VersionSupportTest.php to assert Draft-06 support

Impact:
Schemas using these features can now correctly target Draft-06 instead of being forced to Draft-07+.

// Now works correctly with Draft-06
$schema = Schema::string('content', SchemaVersion::Draft_06)
    ->contentMediaType('application/json')
    ->contentEncoding('base64');

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[Copilot]

Just as a heads up, I was blocked by some firewall rules while working on your feedback. Expand below for details.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• https://api.github.com/repos/Jean85/pretty-package-versions/zipball/4d7aa5dab42e2a76d99559706022885de0e18e1a
  • Triggering command: /usr/bin/php8.3 /usr/bin/php8.3 -n -c /tmp/q4GsUV /usr/bin/composer install (http block)
• https://api.github.com/repos/filp/whoops/zipball/d2102955e48b9fd9ab24280a7ad12ed552752c4d
  • Triggering command: /usr/bin/php8.3 /usr/bin/php8.3 -n -c /tmp/q4GsUV /usr/bin/composer install (http block)
• https://api.github.com/repos/myclabs/DeepCopy/zipball/07d290f0c47959fd5eed98c95ee5602db07e0b6a
  • Triggering command: /usr/bin/php8.3 /usr/bin/php8.3 -n -c /tmp/q4GsUV /usr/bin/composer install (http block)
• https://api.github.com/repos/opis/string/zipball/3e4d2aaff518ac518530b89bb26ed40f4503635e
  • Triggering command: /usr/bin/php8.3 /usr/bin/php8.3 -n -c /tmp/q4GsUV /usr/bin/composer install (http block)
• https://api.github.com/repos/opis/uri/zipball/0f3ca49ab1a5e4a6681c286e0b2cc081b93a7d5a
  • Triggering command: /usr/bin/php8.3 /usr/bin/php8.3 -n -c /tmp/q4GsUV /usr/bin/composer install (http block)
• https://api.github.com/repos/pestphp/pest-plugin/zipball/9d4b93d7f73d3f9c3189bb22c220fef271cdf568
  • Triggering command: /usr/bin/php8.3 /usr/bin/php8.3 -n -c /tmp/q4GsUV /usr/bin/composer install (http block)
• https://api.github.com/repos/php-fig/log/zipball/f16e1d5863e37f8d8c2a01719f5b34baa2b714d3
  • Triggering command: /usr/bin/php8.3 /usr/bin/php8.3 -n -c /tmp/q4GsUV /usr/bin/composer install (http block)
• https://api.github.com/repos/theofidry/cpu-core-counter/zipball/db9508f7b1474469d9d3c53b86f817e344732678
  • Triggering command: /usr/bin/php8.3 /usr/bin/php8.3 -n -c /tmp/q4GsUV /usr/bin/composer install (http block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)