CONTRACT: codingcontract.attempt always returns a string (#231)

* ns.codingcontract always returns a string (reward on success, empty on fail), simplifying usage and documentation of function.
* Because of the above, return value still works when used as a boolean, as long as no direct equality comparison to true/false.
* Documentation expanded and examples added.
Co-authored by @quacksouls

dist/bitburner.d.ts

@@ -651,39 +651,42 @@ export declare interface BladeburnerCurAction {
     name: string;
 }
 
-/**
- * Options to affect the behavior of {@link CodingContract} attempt.
- * @public
- */
-export declare interface CodingAttemptOptions {
-    /** If truthy, then the function will return a string that states the contract’s reward when it is successfully solved. */
-    returnReward: boolean;
-}
-
 /**
  * Coding Contract API
  * @public
  */
 export declare interface CodingContract {
     /**
-     * Attempts a coding contract.
+     * Attempts a coding contract, returning a reward string on success or empty string on failure.
      * @remarks
      * RAM cost: 10 GB
      *
      * Attempts to solve the Coding Contract with the provided solution.
      *
-     * @param answer - Solution for the contract.
+     * @example
+     * ```js
+     * // NS1
+     * var reward = codingcontract.attempt(yourSolution, filename, hostname);
+     * if (reward) {
+     *   tprint("Contract solved successfully! Reward: " + reward)
+     * } else tprint("Failed to solve contract.")
+     * ```
+     * @example
+     * ```js
+     * // NS2
+     * const reward = codingcontract.attempt(yourSolution, filename, hostname);
+     * if (reward) {
+     *   ns.tprint(`Contract solved successfully! Reward: ${reward}`)
+     * } else ns.tprint("Failed to solve contract.")
+     * ```
+     *
+     * @param answer - Attempted solution for the contract.
      * @param filename - Filename of the contract.
-     * @param host - Hostname of the server containing the contract. Optional. Defaults to current server if not provided.
-     * @param opts - Optional parameters for configuring function behavior.
-     * @returns True if the solution was correct, false otherwise. If the returnReward option is configured, then the function will instead return a string. If the contract is successfully solved, the string will contain a description of the contract’s reward. Otherwise, it will be an empty string.
+     * @param host - Hostname of the server containing the contract. Optional. Defaults to current server if not
+     *   provided.
+     * @returns A reward description string on success, or an empty string on failure.
      */
-    attempt(
-    answer: string | number | any[],
-    filename: string,
-    host?: string,
-    opts?: CodingAttemptOptions,
-    ): boolean | string;
+    attempt(answer: string | number | any[], filename: string, host?: string): string;
 
     /**
      * Get the type of a coding contract.