Fix review findings: chi path params, JSON-RPC conformance, SignalR/s…

[mamonth]

…hutdown robustness

Correctness:

• chi v5.2.5 requires {param} braces; OpenAPIPatternToChi no longer rewrites to :id, so OpenAPI/AsyncAPI parameterized routes actually match through the router (was silently broken for every {id} route). Add end-to-end tests.
• JSON-RPC 2.0 conformance: ParseBody returns ordered RpcEntry[] with correct -32600 Invalid Request (was all -32700), malformed batch elements no longer abort siblings, empty batch is invalid, all-notification batches answer 204, and procedure path params are extracted against the procedure's own pattern.
• SignalR delivery: Candidates dedupes per connection (was NxN streams), the negotiate response advertises Text-only matching the handshake, handshake errors are JSON-escaped, and dead removeConnectionStreams is removed.
• Manage-stream sockets get a read deadline (idle reaping); Shutdown cancels pending delayed emissions; state.GetNamespace/GetAll deep-copy nested values.
• /_mock/examples validate (default true) now validates the response body against the route's OpenAPI schema instead of being a silent no-op.

Design:

• Collapse loader/server mirror types to type aliases (RouteMapping, SchemaInfo, RequestRecord, ResponseRecord); delete convert.go and the copy layers.
• Single-source constants: protocol names -> asyncapi.Protocol*, expression source names -> runtime.Source*.
• Consolidate "push to channel" onto the ConsumerBus; central writeJSON helper; pushPayload dead code removed.
• docs/architecture.md and api/openapi.yaml reconciled with implementation; derivedExamples fails loud on a mis-typed match and deep-copies extensions.

Specs: add RS.ASP.11, RS.AMG.29/30, RS.SHR.22, RS.JRP.33/34, RS.MAPI.34 and align RS.SHR.8/RS.JRP.22; 300/300 scenario coverage retained.