[MCP Bundle] Add framework session store backed by SessionHandlerInterface

[simonchrz]

Q	A
Bug fix?	no
New feature?	yes
Docs?	no
License	MIT

Summary

Add a framework session store option that wraps Symfony's SessionHandlerInterface for MCP session persistence.

Extracted from #1791 as requested by @chr-hertel.

FrameworkSessionStore

• Wraps SessionHandlerInterface with a JSON envelope containing data and expiration timestamp
• Application-level TTL with lazy expiry on read (expired sessions destroyed when accessed)
• Does not call SessionHandlerInterface::gc() to avoid affecting framework HTTP sessions
• Configurable prefix (default: mcp-) and TTL (default: 3600s)

Configuration

mcp:
    http:
        session:
            store: framework
            prefix: mcp-
            ttl: 3600

Tests

• FrameworkSessionStoreTest: 11 tests covering read/write round-trip, TTL expiry, invalid envelope handling, destroy delegation, gc no-op, custom prefix, exists checks
• McpBundleTest::testSessionStoreFrameworkConfiguration: verifies DI wiring with session.handler reference

Tested in

Tested in a real Symfony application with the framework session store — works as expected.

[chr-hertel]

Hi! Version 0.7 has been released. This PR has changelog/upgrade entries under the 0.7 heading, which is now a released version.

Please update the following files to place your entries under the next version 0.8:

• src/mcp-bundle/CHANGELOG.md

For CHANGELOG.md files: change the version heading from 0.7 to 0.8
For UPGRADE.md: place entries under UPGRADE FROM 0.7 to 0.8

Thank you!

---

_{🤖 This comment was generated automatically by an agent.}

[chr-hertel]

Thank you @simonchrz.