Port the {.ffi.} wrapper to nim-ffi 0.2.0 (master). 0.2.0 is a breaking
redesign over 0.1.4: events move to a per-context multi-listener registry
(sds_add_event_listener / sds_remove_event_listener) fired via {.ffiEvent.}
emitters, and request/response/event marshalling switches from JSON to CBOR.
- libsds.nim: typed {.ffiEvent.} payloads replace the JSON event modules;
CBOR handles nesting, so unwrap returns a typed response again. The
retrieval-hint provider (a C function pointer, not CBOR-encodable) passes
its address as a uint64 via a {.ffi.} method that stores it in a
worker-thread threadvar.
- pin nim-ffi to master HEAD by commit. The lock version is kept a clean
semver ("0.2.0") on purpose: nimble's `#`-prefixed special version in the
lock breaks `nimble setup -l` (an unquoted `#` truncates the git path),
so only vcsRevision carries the commit.
- add the new transitive dep cbor_serialization to the lock and nix/deps.nix.
- regenerate libsds.h for the CBOR/registry ABI.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Switch the C wrapper from the lower-level registerReqFFI + hand-written
exports to nim-ffi's declareLibrary/{.ffiCtor.}/{.ffi.}/{.ffiDtor.}
macros. This removes the per-op boilerplate (request structs, shared-mem
copy helpers, dispatch template) in favour of the framework's JSON
marshalling, and lets participantId be threaded in via config.
Consequences (intentional): C exports are now snake_case and parameters
travel as JSON, so the ABI changes and sds-go-bindings must be updated to
match. Two cases can't ride the JSON path: the retrieval-hint provider is
a C function pointer (kept hand-written, dispatched to set a worker-thread
threadvar) and the unwrap response has nested objects the framework's
serializer can't emit (returned as a hand-built JSON string).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
