RPC and ZeroMQ APIs to support p2pool

Adds the following:

- "get_miner_data" to RPC API
- "json-miner-data" to ZeroMQ subscriber contexts

Both provide the necessary data to create a custom block template. They are used by p2pool.

Data provided:

- major fork version
- current height
- previous block id
- RandomX seed hash
- network difficulty
- median block weight
- coins mined by the network so far
- mineable mempool transactions

1 files changed, 2 insertions, 0 deletions

diff --git a/src/cryptonote_basic/events.h b/src/cryptonote_basic/events.h
index 6c6742215..3417ece8c 100644
--- a/src/cryptonote_basic/events.h
+++ b/src/cryptonote_basic/events.h
@@ -41,6 +41,8 @@ namespace cryptonote
   {
     cryptonote::transaction tx;
     crypto::hash hash;
+    uint64_t blob_size;
+    uint64_t weight;
     bool res; //!< Listeners must ignore `tx` when this is false.
   };
 }