feat: update TS Bindings stellar-sdk dep to 12rc1

Full release notes at https://github.com/stellar/js-stellar-sdk/releases/tag/v12.0.0-rc.1

Highlights:

- ContractClient now properly handles methods that take no arguments by making MethodOptions the only parameter, bringing it inline with the types generated by Soroban CLI's soroban contract bindings typescript
- ContractClient now allows publicKey to be undefined
- SentTransaction will only pass allowHttp if (and only if) its corresponding AssembledTransaction#options config allowed it

cmd/crates/soroban-spec-typescript/src/project_template/package.json

@@ -1,20 +1,20 @@
 {
-    "version": "0.0.0",
-    "name": "INSERT_CONTRACT_NAME_HERE",
-    "dependencies": {
-        "@stellar/freighter-api": "2.0.0",
-        "buffer": "6.0.3",
-        "@stellar/stellar-sdk": "11.3.0"
-    },
-    "scripts": {
-        "build": "node ./scripts/build.mjs"
-    },
-    "exports": {
-        "require": "./dist/cjs/index.js",
-        "import": "./dist/esm/index.js"
-    },
-    "typings": "dist/types/index.d.ts",
-    "devDependencies": {
-        "typescript": "5.3.3"
-    }
+  "version": "0.0.0",
+  "name": "INSERT_CONTRACT_NAME_HERE",
+  "dependencies": {
+    "@stellar/freighter-api": "2.0.0",
+    "buffer": "6.0.3",
+    "@stellar/stellar-sdk": "12.0.0-rc.1"
+  },
+  "scripts": {
+    "build": "node ./scripts/build.mjs"
+  },
+  "exports": {
+    "require": "./dist/cjs/index.js",
+    "import": "./dist/esm/index.js"
+  },
+  "typings": "dist/types/index.d.ts",
+  "devDependencies": {
+    "typescript": "5.3.3"
+  }
 }