push_back(std::nullopt) and remove unnecessary lint disablers

[wujingyue]

https://abseil.io/tips/112

[wujingyue]

!test

[github-actions]

Review updated until commit 5131437

Description

• Replace emplace_back with push_back for clarity

• Remove unnecessary NOLINT comment

• Simplify contiguity vector initialization

• Improve code readability and consistency

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Changes walkthrough 📝

	Relevant files
Enhancement	alias_analysis.cpp Replace emplace_back with push_back                                            csrc/alias_analysis.cpp Use push_back instead of emplace_back No functional change, improves readability +1/-1      nodes.cpp Use push_back for optional vector                                    csrc/ir/nodes.cpp Replace emplace_back with push_back Maintain same logic for optional values +1/-1
Miscellaneous	transform_replay.cpp Remove unused lint disabler comment                                            csrc/transform_replay.cpp Remove unnecessary NOLINT comment Keep push_back usage consistent +0/-1

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PR Reviewer Guide 🔍

Here are some key observations to aid the review process:

🧪 No relevant tests

⚡ No major issues detected

[wujingyue]

!build