[Examples] Demo pre-built instance handlers + inspector coverage (#390)

* [Tests] Bump MCP Inspector to 0.22.0 for 2025-11-25 protocol

The pinned inspector 0.17.2 predates the protocol version bump to
2025-11-25 (v0.6.0) and rejects the handshake with "Server's protocol
version is not supported", failing every inspector snapshot test. 0.22.0
negotiates the current protocol; the full inspector suite passes against
it (95 tests, 7 pre-existing skips).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

* [Examples] Demo pre-built instance handler in combined-registration

Extends the combined-registration example with a third handler style:
a pre-built object instance `[$instance, 'method']`, alongside the
existing discovered and manual class-string handlers. PreconfiguredGreeter
takes a scalar constructor argument neither the container-less
`new $className()` fallback nor the auto-wiring container can build, so it
can only be registered as an already-constructed instance — exercising the
resolver path added in the parent branch.

Adds an inspector snapshot case (tools/call instance_greeter) and updates
the tools/list snapshot.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

tests/Inspector/InspectorSnapshotTestCase.php

@@ -18,7 +18,7 @@ use Symfony\Component\Process\Process;
 
 abstract class InspectorSnapshotTestCase extends TestCase
 {
-    private const INSPECTOR_VERSION = '0.17.2';
+    private const INSPECTOR_VERSION = '0.22.0';
 
     /** @param array<string, mixed> $options */
     #[DataProvider('provideMethods')]