Update: new version rand -> 0.9.2 and change code syntax.

[mohitnandaniya-devloper]

This pull request finalizes the code for the Chapter 2 guessing game tutorial, implementing the completed logic across the sequential steps (02-02 through 02-06).

Changes Included:

1. Code Implementation: The src/main.rs file in the listing directory was updated with the full, final guessing game logic, combining the steps for input, random number generation (secret_number), looping, and comparison using match.
2. Dependency Update: The rand crate version was updated to 0.9.2 in the project manifest (listings/ch02-guessing-game-tutorial/listing-02-02/Cargo.toml).
3. CI Test Fix: The rand = "0.9.2" dependency was added to packages/trpl/Cargo.toml to ensure the book's embedded Rust documentation tests (doctests) can successfully compile and run, resolving the previous unresolved import rand error.

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Why

The purpose of this contribution is three-fold: to ensure the educational content is complete, to maintain dependency hygiene, and to fix a critical test failure in the continuous integration (CI) pipeline.

1. Educational Logic Completion: This PR provides the accurate, final source code corresponding to the end of the "Programming a Guessing Game" chapter, ensuring the example is fully functional for all readers.
2. Project Health & Dependency Maintenance: It updates a core non-standard library dependency (rand) to a newer version, which is a key part of routine maintenance.
3. Resolves CI/Test Failure: The dependency change in packages/trpl/Cargo.toml resolves a compilation error in the book's test harness, ensuring the overall repository test suite remains healthy and passes.

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Verification

All code has been locally compiled, formatted (rustfmt, dprint), and verified to run correctly.

[mohitnandaniya-devloper]

Hi team! I'm following up on this PR. I previously submitted a request that was deleted along with its branch. This new PR incorporates the feedback from the previous request (specifically the query about [ @olino03 - The markdown files are not updated correctly. There's a section named 'Updating a Crate to Get a New Version' where it builds up knowledge related to how crate versions are handled which also would need updating.]). Let me know if any further changes are needed! Thanks!