feat(receive): Add tests for InputPair constructors Closes #583

[Johnosezele]

Add unit tests for the new_p2wpkh and new_p2tr constructors within the receive module (payjoin/src/receive/mod.rs). These tests verify that the constructors correctly initialize the InputPair struct, ensuring both the TxIn and psbt::Input components match expected values.

This improves code quality by confirming constructor behavior and guarding against regressions.

Also addresses compilation errors found during testing:

• Corrected call to new_p2wpkh to include the sequence argument.
• Removed assertions checking non-existent fields on psbt::Input (e.g., script_sig, tap_control_block).
• Renamed tap_leaf_scripts to the correct field tap_scripts in assertions.

[coveralls]

Pull Request Test Coverage Report for Build 14538496834

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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Details

• 399 of 405 (98.52%) changed or added relevant lines in 1 file are covered.
• 2 unchanged lines in 1 file lost coverage.
• Overall coverage increased (+1.0%) to 82.798%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
payjoin/src/receive/mod.rs	399	405	98.52%
<!--	Total:	399	405

Files with Coverage Reduction	New Missed Lines	%
payjoin/src/send/mod.rs	2	94.46%
<!--	Total:	2

Totals
Change from base Build 14519980933:	1.0%
Covered Lines:	5723
Relevant Lines:	6912

---

💛 - Coveralls

[Johnosezele]

PR Updated:

• Removed test_new_p2wpkh as suggested
• Cleaned up test comments for better readability
• All tests are passing
• Added comprehensive test coverage:
  • test_privacy_based_input_selection: Tests UIH avoidance
  • test_fee_rate_based_selection: Validates fee rate enforcement
  • test_minimum_fee_requirements: Tests end-to-end fee handling

Ready for another review! 👍

[spacebear21]

Closing this as it has been mainly addressed by #712 #753, with some small follow-ups still needed.