fix(logging): 🐛 improve RUST_LOG env var parsing to fix default log level

[HayWolf]

Summary

• Replace EnvFilter::try_from_default_env() with explicit std::env::var("RUST_LOG") check in init_logging()
• Fix an issue where tiycore warn logs were not captured to log files unless RUST_LOG was explicitly set
• The previous try_from_default_env() API in tracing-subscriber 0.3.23 did not reliably error when RUST_LOG was unset, causing the default info level fallback to never trigger

Changes

• src-tauri/src/lib.rs: Replace EnvFilter::try_from_default_env() fallback pattern with explicit match std::env::var("RUST_LOG") guard, ensuring the default info,sqlx=warn filter is correctly applied when RUST_LOG is not set

Test Plan

• Verify tiycore warn logs appear in log files without setting RUST_LOG
• Verify RUST_LOG=tiycore=debug still works to override default level
• Verify invalid RUST_LOG values fall back to default gracefully

🤖 Generated with TiyCode

[github-actions]

AI Code Review Summary

PR: #158 (fix(logging): 🐛 improve RUST_LOG env var parsing to fix default log level)
Preferred language: English

Overall Assessment

No blocking issue was detected in the reviewed diff; keep focused regression testing before merge.

Major Findings by Severity

No major issues identified from the reviewed diff.

Actionable Suggestions

• Add a comment clarifying the intended behavior for an empty RUST_LOG vs. unset RUST_LOG.

Potential Risks

• Potential hidden risks remain in edge cases not covered by the current diff context.

Test Suggestions

• Add happy-path + boundary + failure-path tests for touched modules.

File-Level Coverage Notes

• src-tauri/src/lib.rs: mostly safe with one minor behavior change to note

Inline Downgraded Items (processed but not inline)

• None

Coverage Status

• Target files: 1
• Covered files: 1
• Uncovered files: 0
• No-patch/binary covered as file-level: 0
• Findings with unknown confidence (N/A): 0

Uncovered list:

• None

No-patch covered list:

• None

Runtime/Budget

• Rounds used: 1/4
• Planned batches: 1
• Executed batches: 1
• Sub-agent runs: 1
• Planner calls: 1
• Reviewer calls: 1
• Model calls: 2/64
• Structured-output summary-only degradation: NO

[github-actions]

Automated PR review completed.

• Findings kept: 0
• Findings with unknown confidence: 0
• Inline comments attempted: 1
• Target files: 1
• Covered files: 1
• Uncovered files: 0
  See the summary comment for detailed analysis and coverage details.

[github-actions]

Automated review completed for this PR diff. No concrete inline issue was selected after aggregation.