[Server] Oauth2 based on middleware (#221)

* Add Middleware handlers to StreamableHttpTransport

* OAuth Implementation based on middleware

* OAuth Implementation based on middleware

* Add Middleware handlers to StreamableHttpTransport

* OAuth Implementation based on middleware

* OAuth Implementation based on middleware

Signed-off-by: Volodymyr Panivko <sveneld300@gmail.com>

* Address PR review feedback for OAuth middleware

* Apply php-cs-fixer to satisfy QA

* Use Mcp exception classes in OAuth middleware

* Refactor OAuth HTTP stack and add Microsoft example policies

* Fix QA PHPStan findings in OAuth examples and auth middleware

* Require OIDC discovery in JWKS provider and refine OAuth proxy behavior

* Remove local development docker artifacts from VCS

* Revert .gitignore changes for local docker files

* Fix body retrieval in OAuthRequestMetaMiddleware for proper string conversion

Signed-off-by: Volodymyr Panivko <sveneld300@gmail.com>

* Address OAuth PR review feedback and align example configs

* Fix QA style issues and add authorization docs

* Fix PHPStan typing issues in OAuth middleware

* Remove duplicate Middleware namespace, consolidate under Http\Middleware

Remove old Mcp\Server\Transport\Middleware\ classes that were duplicated
in Mcp\Server\Transport\Http\Middleware\ and Http\OAuth\. Update docs
to reference the correct namespaces.

* Address PR review: replace Throwable catch with specific exceptions, add JSON_THROW_ON_ERROR

- JwtTokenValidator: replace catch(\Throwable) with explicit
  \InvalidArgumentException|\UnexpectedValueException|\DomainException,
  letting RuntimeException from JwksProvider propagate as infrastructure errors
- OAuthProxyMiddleware: add \JSON_THROW_ON_ERROR to json_encode for metadata response
- Update tests to expect RuntimeException for JWKS infrastructure failures

---------

Signed-off-by: Volodymyr Panivko <sveneld300@gmail.com>
Co-authored-by: Volodymyr Panivko <volodymyr.panivko@togethernetworks.com>

Author: sveneld

composer.json

@@ -26,6 +26,7 @@
     "psr/clock": "^1.0",
     "psr/container": "^1.0 || ^2.0",
     "psr/event-dispatcher": "^1.0",
+    "psr/http-client": "^1.0",
     "psr/http-factory": "^1.1",
     "psr/http-message": "^1.1 || ^2.0",
     "psr/http-server-handler": "^1.0",
@@ -35,6 +36,8 @@
     "symfony/uid": "^5.4 || ^6.4 || ^7.3 || ^8.0"
   },
   "require-dev": {
+    "ext-openssl": "*",
+    "firebase/php-jwt": "^6.10 || ^7.0",
     "laminas/laminas-httphandlerrunner": "^2.12",
     "nyholm/psr7": "^1.8",
     "nyholm/psr7-server": "^1.1",
@@ -46,6 +49,7 @@
     "psr/simple-cache": "^2.0 || ^3.0",
     "symfony/cache": "^5.4 || ^6.4 || ^7.3 || ^8.0",
     "symfony/console": "^5.4 || ^6.4 || ^7.3 || ^8.0",
+    "symfony/http-client": "^5.4 || ^6.4 || ^7.3 || ^8.0",
     "symfony/process": "^5.4 || ^6.4 || ^7.3 || ^8.0"
   },
   "autoload": {
@@ -68,6 +72,8 @@
       "Mcp\\Example\\Server\\DiscoveryUserProfile\\": "examples/server/discovery-userprofile/",
       "Mcp\\Example\\Server\\EnvVariables\\": "examples/server/env-variables/",
       "Mcp\\Example\\Server\\ExplicitRegistration\\": "examples/server/explicit-registration/",
+      "Mcp\\Example\\Server\\OAuthKeycloak\\": "examples/server/oauth-keycloak/",
+      "Mcp\\Example\\Server\\OAuthMicrosoft\\": "examples/server/oauth-microsoft/",
       "Mcp\\Example\\Server\\SchemaShowcase\\": "examples/server/schema-showcase/",
       "Mcp\\Tests\\": "tests/"
     }