Optimize internal u8a decoding (#4131)

* Optimize internal u8a decoding

* linting

* tsc fixes & HexString usage

* yet more... it passes now (well... tsc & lint)

yarn.lock

@@ -1874,9 +1874,9 @@ __metadata:
   languageName: unknown
   linkType: soft
 
-"@polkadot/dev@npm:^0.63.10":
-  version: 0.63.10
-  resolution: "@polkadot/dev@npm:0.63.10"
+"@polkadot/dev@npm:^0.63.18":
+  version: 0.63.18
+  resolution: "@polkadot/dev@npm:0.63.18"
   dependencies:
     "@babel/cli": ^7.15.7
     "@babel/core": ^7.15.8
@@ -1902,10 +1902,10 @@ __metadata:
     "@rollup/plugin-inject": ^4.0.3
     "@rollup/plugin-json": ^4.1.0
     "@rollup/plugin-node-resolve": ^13.0.6
-    "@rushstack/eslint-patch": ^1.0.8
+    "@rushstack/eslint-patch": ^1.0.9
     "@typescript-eslint/eslint-plugin": 5.2.0
     "@typescript-eslint/parser": 5.2.0
-    "@vue/component-compiler-utils": ^3.2.2
+    "@vue/component-compiler-utils": ^3.3.0
     babel-jest: ^27.3.1
     babel-plugin-module-extension-resolver: ^1.0.0-rc.2
     babel-plugin-module-resolver: ^4.1.0
@@ -1964,7 +1964,7 @@ __metadata:
     polkadot-exec-rollup: scripts/polkadot-exec-rollup.cjs
     polkadot-exec-tsc: scripts/polkadot-exec-tsc.cjs
     polkadot-exec-webpack: scripts/polkadot-exec-webpack.cjs
-  checksum: a47ef588d69c35d67fb96ffc8a386de1d5c722dd9817068cc063e0d634c4e9f356e937d572eb46bfdcbd28a4e9822c9469cb6cab8ec2eda024e0053b7d31e63a
+  checksum: 76c73b040bb02e9b1d7b050718e1e9b8bad4a20850b33e9597d0ccc07981e79c18f19ff3d1b4ab2827b86fe7fede8ee11f83b3ecf3518de7e294164de4b1c130
   languageName: node
   linkType: hard
 
@@ -2310,10 +2310,10 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@rushstack/eslint-patch@npm:^1.0.8":
-  version: 1.0.8
-  resolution: "@rushstack/eslint-patch@npm:1.0.8"
-  checksum: e1c4e2d8317db712a4f24510eacb98c13fd18632eaffae0096a359ab02021ce44c35f614d489741e57f4b0f2d8b11b4b95cdc00aa57753d840d0ba512a5c609e
+"@rushstack/eslint-patch@npm:^1.0.9":
+  version: 1.0.9
+  resolution: "@rushstack/eslint-patch@npm:1.0.9"
+  checksum: 01425d38261013955990e4e923bc57dd1ff258a09740a5cbf5645b6a61cd3c85255edd11801277c07022fabbdfdb39d1d324f6acb1bc0b1795d2a0a187b9569f
   languageName: node
   linkType: hard
 
@@ -2740,9 +2740,9 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@vue/component-compiler-utils@npm:^3.2.2":
-  version: 3.2.2
-  resolution: "@vue/component-compiler-utils@npm:3.2.2"
+"@vue/component-compiler-utils@npm:^3.3.0":
+  version: 3.3.0
+  resolution: "@vue/component-compiler-utils@npm:3.3.0"
   dependencies:
     consolidate: ^0.15.1
     hash-sum: ^1.0.2
@@ -2750,13 +2750,13 @@ __metadata:
     merge-source-map: ^1.1.0
     postcss: ^7.0.36
     postcss-selector-parser: ^6.0.2
-    prettier: ^1.18.2
+    prettier: ^1.18.2 || ^2.0.0
     source-map: ~0.6.1
     vue-template-es2015-compiler: ^1.9.0
   dependenciesMeta:
     prettier:
       optional: true
-  checksum: ae2d08b4c1907c1bdb2c35e0d67e58afd3afa053bbc5f9cdb6de8915b051124d034cd6b14808aca5c93776289dd832e5514847e4fb925571857aa237262d753a
+  checksum: 70fee2289a4f54ec1be4d46136ee9b9893e31bf5622cead5be06c3dfb83449c3dbe6f8c03404625ccf302d0628ff9e2ea1debfae609d1bfe1d065d8f57c5dba8
   languageName: node
   linkType: hard
 
@@ -8390,16 +8390,7 @@ fsevents@~2.1.2:
   languageName: node
   linkType: hard
 
-"prettier@npm:^1.18.2":
-  version: 1.19.1
-  resolution: "prettier@npm:1.19.1"
-  bin:
-    prettier: ./bin-prettier.js
-  checksum: bc78219e0f8173a808f4c6c8e0a137dd8ebd4fbe013e63fe1a37a82b48612f17b8ae8e18a992adf802ee2cf7428f14f084e7c2846ca5759cf4013c6e54810e1f
-  languageName: node
-  linkType: hard
-
-"prettier@npm:^2.4.1":
+"prettier@npm:^1.18.2 || ^2.0.0, prettier@npm:^2.4.1":
   version: 2.4.1
   resolution: "prettier@npm:2.4.1"
   bin:
@@ -8952,7 +8943,7 @@ resolve@^2.0.0-next.3:
     "@babel/core": ^7.15.8
     "@babel/register": ^7.15.3
     "@babel/runtime": ^7.15.4
-    "@polkadot/dev": ^0.63.10
+    "@polkadot/dev": ^0.63.18
     "@polkadot/ts": ^0.4.12
     "@polkadot/typegen": "workspace:packages/typegen"
     "@types/jest": ^27.0.2