add support for mint decimals on bank, for easy look up

Signed-off-by: microwavedcola1 <microwavedcola@gmail.com>

programs/mango-v4/src/instructions/register_token.rs

@@ -131,6 +131,7 @@ pub fn register_token(
         token_index,
         bump: *ctx.bumps.get("bank").ok_or(MangoError::SomeError)?,
         reserved: Default::default(),
+        mint_decimals: ctx.accounts.mint.decimals,
     };
 
     // TODO: ALTs are unavailable

programs/mango-v4/src/state/bank.rs

@@ -61,7 +61,9 @@ pub struct Bank {
 
     pub bump: u8,
 
-    pub reserved: [u8; 5],
+    pub mint_decimals: u8,
+
+    pub reserved: [u8; 4],
 }
 const_assert_eq!(size_of::<Bank>(), 16 + 32 * 4 + 8 + 16 * 18 + 3 + 5);
 const_assert_eq!(size_of::<Bank>() % 8, 0);

ts/client/src/accounts/bank.ts

@@ -39,6 +39,7 @@ export class Bank {
       liquidationFee: I80F48Dto;
       dust: Object;
       tokenIndex: number;
+      mintDecimals: number;
     },
   ) {
     return new Bank(
@@ -68,6 +69,7 @@ export class Bank {
       obj.liquidationFee,
       obj.dust,
       obj.tokenIndex,
+      obj.mintDecimals,
     );
   }
 
@@ -98,6 +100,7 @@ export class Bank {
     liquidationFee: I80F48Dto,
     dust: Object,
     public tokenIndex: number,
+    public mintDecimals: number,
   ) {
     this.name = utf8.decode(new Uint8Array(name)).split('\x00')[0];
     this.depositIndex = I80F48.from(depositIndex);

ts/client/src/mango_v4.ts

@@ -1730,12 +1730,16 @@ export type MangoV4 = {
             "name": "bump",
             "type": "u8"
           },
+          {
+            "name": "mintDecimals",
+            "type": "u8"
+          },
           {
             "name": "reserved",
             "type": {
               "array": [
                 "u8",
-                5
+                4
               ]
             }
           }
@@ -4626,12 +4630,16 @@ export const IDL: MangoV4 = {
             "name": "bump",
             "type": "u8"
           },
+          {
+            "name": "mintDecimals",
+            "type": "u8"
+          },
           {
             "name": "reserved",
             "type": {
               "array": [
                 "u8",
-                5
+                4
               ]
             }
           }