update mqtt5 to 0.48.1 and mqdb-agent to 0.8.37, resume sessions and fix native projection

[fabracht]

Updates mqtt5 to 0.48.1, mqtt5-protocol to 0.16.1, mqtt5-wasm to 2.1.7, mqdb-agent to 0.8.37, mqdb-core to 0.7.12 and mqdb-wasm to 0.3.6. Native builds now carry a single mqtt5.

• Sessions resume across restarts: since mqtt5 0.41 a new client that finds a stored session refuses the connection unless asked to resume. stitch keeps sessions (clean_start: false, 3600 s expiry), so native and wasm now set resume_existing_session whenever clean_start is off.
• Broker disconnects with NotAuthorized, BadUsernameOrPassword or BadAuthenticationMethod report an auth failure; other new events map to disconnected.
• mqtt5-wasm 2.x snake_case setters and publishWithOptions return value.
• Native Store::list applies its projection (it was passed as mqdb's relationship includes).
• rustls 0.23.46 for the open Dependabot alert; mqp2p and stitch-wasm MSRV 1.89.
• CI runs all stitch-sync and stitch-harness tests, including broker_harness.

Tests: restarted_store_with_the_same_client_id_resumes_its_session and list_with_projection_returns_only_projected_fields, each failing without its fix. Workspace: 230 passed, 0 failed; wasm browser tests 22/22 (headless Firefox).