feat: prepare MM backend stuff (#6448)

Description
---
This removes a few panics, and adds in a fake mainnet block.
Duplicates stagenet consensus values for mainnet. 

Motivation and Context
---
As we are getting closer to mainnet, we need to ensure that we can test
all of the features. This adds in a temporary mainnet block to use in
local testing. This block will not be the final one and will only be a
place holder.

How Has This Been Tested?
---
unit tests

---------

Co-authored-by: Hansie Odendaal <[email protected]>

applications/minotari_console_wallet/src/automation/commands.rs

@@ -2351,7 +2351,7 @@ fn create_pre_mine_output_dir() -> Result<(String, PathBuf), CommandError> {
 fn get_embedded_pre_mine_outputs(output_indexes: Vec<usize>) -> Result<Vec<TransactionOutput>, CommandError> {
     let pre_mine_contents = match Network::get_current_or_user_setting_or_default() {
         Network::MainNet => {
-            unimplemented!("MainNet pre-mine not yet implemented");
+            include_str!("../../../../base_layer/core/src/blocks/pre_mine/mainnet_pre_mine.json")
         },
         Network::StageNet => {
             include_str!("../../../../base_layer/core/src/blocks/pre_mine/stagenet_pre_mine.json")

applications/minotari_miner/src/run_miner.rs

@@ -114,18 +114,24 @@ pub async fn start_miner(cli: Cli) -> Result<(), ExitError> {
         if !config.mining_worker_name.is_empty() {
             miner_address += &format!("{}{}", ".", config.mining_worker_name);
         }
-        let mut mc = Controller::new(config.num_mining_threads).unwrap_or_else(|e| {
+        let mut mc = Controller::new(config.num_mining_threads).map_err(|e| {
             debug!(target: LOG_TARGET_FILE, "Error loading mining controller: {}", e);
-            panic!("Error loading mining controller: {}", e);
-        });
+            ExitError::new(
+                ExitCode::UnknownError,
+                format!("Error loading mining controller: {}", e),
+            )
+        })?;
         let cc = crate::stratum::controller::Controller::new(&url, Some(miner_address), None, None, mc.tx.clone())
-            .unwrap_or_else(|e| {
+            .map_err(|e| {
                 debug!(
                     target: LOG_TARGET_FILE,
                     "Error loading stratum client controller: {:?}", e
                 );
-                panic!("Error loading stratum client controller: {:?}", e);
-            });
+                ExitError::new(
+                    ExitCode::UnknownError,
+                    format!("Error loading mining controller: {}", e),
+                )
+            })?;
         mc.set_client_tx(cc.tx.clone());
 
         let _join_handle = thread::Builder::new()

base_layer/core/src/blocks/genesis_block.rs

@@ -209,7 +209,50 @@ fn get_nextnet_genesis_block_raw() -> Block {
 }
 
 pub fn get_mainnet_genesis_block() -> ChainBlock {
-    unimplemented!()
+    let mut block = get_mainnet_genesis_block_raw();
+
+    // Add pre-mine utxos - enable/disable as required
+    let add_pre_mine_utxos = false;
+    if add_pre_mine_utxos {
+        // NB: `stagenet_genesis_sanity_check` must pass
+        let file_contents = include_str!("pre_mine/mainnet_pre_mine.json");
+        add_pre_mine_utxos_to_genesis_block(file_contents, &mut block);
+        // Enable print only if you need to generate new Merkle roots, then disable it again
+        let print_values = false;
+        print_mr_values(&mut block, print_values);
+
+        // Hardcode the Merkle roots once they've been computed above
+        block.header.kernel_mr =
+            FixedHash::from_hex("a08ff15219beea81d4131465290443fb3bd99d28b8af85975dbb2c77cb4cb5a0").unwrap();
+        block.header.output_mr =
+            FixedHash::from_hex("435f13e21be06b0d0ae9ad3869ac7c723edd933983fa2e26df843c82594b3245").unwrap();
+        block.header.validator_node_mr =
+            FixedHash::from_hex("277da65c40b2cf99db86baedb903a3f0a38540f3a94d40c826eecac7e27d5dfc").unwrap();
+    }
+
+    let accumulated_data = BlockHeaderAccumulatedData {
+        hash: block.hash(),
+        total_kernel_offset: block.header.total_kernel_offset.clone(),
+        achieved_difficulty: Difficulty::min(),
+        total_accumulated_difficulty: 1.into(),
+        accumulated_randomx_difficulty: AccumulatedDifficulty::min(),
+        accumulated_sha3x_difficulty: AccumulatedDifficulty::min(),
+        target_difficulty: Difficulty::min(),
+    };
+    ChainBlock::try_construct(Arc::new(block), accumulated_data).unwrap()
+}
+
+fn get_mainnet_genesis_block_raw() -> Block {
+    // Set genesis timestamp
+    let genesis_timestamp = DateTime::parse_from_rfc2822("05 Aug 2024 08:00:00 +0200").expect("parse may not fail");
+    let not_before_proof = b"I am the standin mainnet genesis block, \
+        \
+       I am not the real mainnet block \
+        \
+        I am only a standin \
+        \
+       Do not take me for the real one. I am only a placeholder for the real one";
+    get_raw_block(&genesis_timestamp, &not_before_proof.to_vec())
 }
 
 pub fn get_igor_genesis_block() -> ChainBlock {