Add CodSpeed performance benchmarks for Rust domain layer

[codspeed-hq]

What this PR does

Integrates CodSpeed continuous performance tracking into the Vortex project, benchmarking the Rust domain layer — the pure business logic at the core of the application.

Benchmarks added

22 benchmarks across 7 groups covering the critical domain model operations:

Group	Benchmarks	What's measured
url_parsing	4	HTTPS, complex URLs with ports/query params, userinfo, FTP scheme
download_state_machine	5	Creation, full lifecycle, retry cycles, progress calculation, checksum workflow
segment_operations	4	Creation, full lifecycle, segment splitting, error/reset cycles
checksum_detection	3	SHA-256 detection, MD5 detection, invalid input rejection
link_status	3	HTTP status code mapping (200, 404, 500)
config_operations	5	Default creation, single/multi-field patching, normalization functions
priority	2	Valid and invalid priority creation

Why the domain layer?

The domain layer (src-tauri/src/domain/model/) implements core business logic with zero external dependencies — making it ideal for deterministic CPU simulation benchmarks. These operations are called on every download interaction, so regressions here directly impact user experience.

Changes

• src-tauri/benches/domain_benchmarks.rs — Criterion benchmark suite with CodSpeed compatibility
• src-tauri/Cargo.toml — Added codspeed-criterion-compat dev dependency and bench target
• .github/workflows/codspeed.yml — GitHub Actions workflow for continuous performance tracking (simulation mode, OIDC auth)
• README.md — Added CodSpeed performance badge

How it works

CodSpeed runs benchmarks in simulation mode, using CPU instruction counting for deterministic, reproducible measurements with <1% variance — no need for dedicated hardware. The GitHub Actions workflow runs on every push to main and on pull requests, providing automatic performance regression detection.

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Summary by cubic

Adds CodSpeed benchmarks for the Rust domain layer, with a CI workflow that runs on pushes and PRs to catch performance regressions. Adds a README badge and CHANGELOG entry; benches run from src-tauri.

• New Features

  • Benchmark suite at src-tauri/benches/domain_benchmarks.rs using codspeed-criterion-compat.
  • 26 benchmarks across 7 groups: url_parsing, download_state_machine, segment_operations, checksum_detection, link_status, config_operations, priority.
  • GitHub Actions workflow runs CodSpeed in simulation mode on main and PRs; builds and runs via cargo-codspeed from src-tauri. Adds README badge and updates CHANGELOG.
  • Adds dev dependency criterion (package codspeed-criterion-compat) and a bench target (domain_benchmarks) in Cargo.toml.

• Bug Fixes

  • CI uses job working-directory and runs benches from src-tauri, fixing cargo-codspeed execution.
  • Applied rustfmt and reordered Criterion imports to match 2024 edition rules.

^{Written for commit c3a7733. Summary will update on new commits.}

[codspeed-hq]

Congrats! CodSpeed is installed 🎉

🆕 26 new benchmarks were detected.

You will start to see performance impacts in the reports once the benchmarks are run from your default branch.

Detected benchmarks

• detect_sha256: 821.9 ns
• default_config: 3.1 µs
• create_invalid: 2.6 µs
• create_valid: 312.5 ns
• normalize_max_concurrent: 179.2 ns
• start_and_fail_retry_cycle: 5.1 µs
• full_lifecycle: 225.6 ns
• create_new: < 1 ns
• reject_invalid: 581.1 ns
• apply_patch_many_fields: 3.7 µs
• full_lifecycle: 4.2 µs
• progress_percentage: 393.9 ns
• detect_md5: 657.5 ns
• checksum_workflow: 6.6 µs
• from_status_code_500: 96.1 ns
• from_status_code_404: 154.7 ns
• simple_https: 2.7 µs
• split: 471.9 ns
• apply_patch_single_field: 3 µs
• normalize_link_check_parallelism: 150 ns
• ...

ℹ️ Only the first 20 benchmarks are displayed. Go to the app to view all benchmarks.

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[cubic-dev-ai]

No issues found across 5 files