* chore: export subscriptions
This has a knock-on effect of nim-serde not being imported into subscriptions when JsonRpcProvider.new is called from a consumer that does not export nim-serde.
* import/export serde
* Replace all instances of std/json with pkg/serde
* fix: modify unsubscribe cleanup routine
Ignore exceptions (other than CancelledError) if uninstallation of the filter fails. If it's the last step in the subscription cleanup, then filter changes for this filter will no longer be polled so if the filter continues to live on in geth for whatever reason, then it doesn't matter.
This includes a number of fixes:
- `CancelledError` is now caught inside of `getChanges`. This was causing conditions during `subscriptions.close`, where the `CancelledError` would get consumed by the `except CatchableError`, if there was an ongoing `poll` happening at the time of close.
- After creating a new filter inside of `getChanges`, the new filter is polled for changes before returning.
- `getChanges` also does not swallow `CatchableError` by returning an empty array, and instead re-raises the error if it is not `filter not found`.
- The tests were simplified by accessing the private fields of `PollingSubscriptions`. That way, there wasn't a race condition for the `newFilterId` counter inside of the mock.
- The `MockRpcHttpServer` was simplified by keeping track of the active filters only, and invalidation simply removes the filter. The tests then only needed to rely on the fact that the filter id changed in the mapping.
- Because of the above changes, we no longer needed to sleep inside of the tests, so the sleeps were removed, and the polling interval could be changed to 1ms, which not only makes the tests faster, but would further highlight any race conditions if present.
* docs: rpc custom port documentation
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Co-authored-by: Adam Uhlíř <adam@uhlir.dev>
