Declare minimum compatible majors for fastmcp and faststream #175

[project.optional-dependencies] pins a floor where one is known to matter —
litestar>=2.15, prometheus-fastapi-instrumentator>=8.0.1, prometheus-client>=0.20,
opentelemetry-instrumentation-asgi>=0.46b0 — but fastmcp and faststream are declared bare.
Both bootstrappers reach into framework internals that a major bump could move:
FastMcpBootstrapper registers a _TeardownProvider through add_provider()
(docs/adr/0001-fastmcp-teardown-via-provider-lifespan.md), and FastStreamBootstrapper mutates
broker.config.logger.params_storage and calls broker.ping(timeout=...).

lite-bootstrap is a library distributed to downstream services, so an unpinned major means a
breaking upstream release resolves into a user's environment and fails at their bootstrap, not in
our CI. Establish the lowest version each bootstrapper is actually tested against and declare it,
the way litestar>=2.15 already documents which two APIs forced that floor.

Revisit trigger: a fastmcp or faststream major release, or the first user report of a
bootstrap failing against a version this repo never tested.