Added basics/processing-instructions/poseidon

[ritikbhatt20]

Key Differences from previous processing-instructions PRs:

• Poseidon Transpiler lacks support for logging msgs in Solana Programs from Poseidon. The logging functionality provided by console.log() calls is not preserved and not converted to msg! in Anchor, so this is done manually in lib.rs.
  I have raised issue to poseidon for this: Lack of Support for Logging Messages from console.log to msg! in Poseidon Turbin3/poseidon#26
• As i abided by the exact same structure with the Anchor code, the resulting transpiled Rust code includes a 'info lifetime parameter in the context struct even when it is not used. This causes an error during the Anchor build process.
  Raised issue to poseidon for this: Issue: Unused 'info Parameter in Transpiled Anchor Code Turbin3/poseidon#29
  Edit- Issue resolved 🚀🚀
• Followed the original exact program structure from the processing-instructions example in Anchor, ensuring consistency which some previous PR's didn't follow.
• Includes both Anchor and Bankrun tests, providing comprehensive test coverage that was missing in previous PRs.

Moreover:
added an example for processing-instructions Poseidon program in the /basics/processing-instructions/poseidon directory.

replaced all occurrences of yarn with pnpm to maintain consistency across the project.

executed pnpm fix to ensure code quality.

committed the pnpm-lock.yaml file to the repository.

[heyAyushh]

Thanks for your submission! To verify the technical implementation, please complete these steps:

1. Merge the main branch into your PR to get the latest updates
2. Run pnpm fix at the project root for consistent code style
3. Ensure your implementation includes:
   • Transpiled Anchor program in the programs folder
   • TypeScript files in the ts-programs folder
4. Run poseidon sync to synchronize program ID and keys
5. Run cargo fmt and cargo clippy for Rust code quality
6. Push your changes

Please note: This review is to verify technical completeness of the submission

Let me know once you've completed these steps and I'll review again. Thanks!

[ritikbhatt20]

Thanks for your submission! To verify the technical implementation, please complete these steps:

1. Merge the main branch into your PR to get the latest updates

2. Run pnpm fix at the project root for consistent code style

3. Ensure your implementation includes:

   • Transpiled Anchor program in the programs folder
   • TypeScript files in the ts-programs folder

4. Run poseidon sync to synchronize program ID and keys

5. Run cargo fmt and cargo clippy for Rust code quality

6. Push your changes

Please note: This review is to verify technical completeness of the submission

Let me know once you've completed these steps and I'll review again. Thanks!

gm @heyAyushh ,

I've completed the requested steps:

1. Merged main into my branch.
2. Ran pnpm fix.
3. Verified the implementation includes the transpiled Anchor program and TypeScript files.
4. Synchronized program ID
5. Ran cargo fmt and cargo clippy for Rust code quality.
6. Pushed all updates.

Please review again. Thank you!

[ritikbhatt20]

gm @heyAyushh ,

I have refactored the changes according to new Poseidon Str type..
please review again thanks!

[heyAyushh]

LGTM