perf(dev): reduce Rust debug build cost

[johnmatthewtennant]

Summary

Use line-table-only debug information for local Rust builds. File and line backtraces remain available, while CARGO_PROFILE_DEV_DEBUG=2 restores full debugger locals when needed.

Give Rust Analyzer its own target directory so background analysis does not contend with interactive Cargo builds in the same checkout.

Verification

On a clean Blox checkout, cargo build --manifest-path src-tauri/Cargo.toml --workspace improved from 76.19 seconds and 7.8 GB with full debug information to 66.78 seconds and 4.9 GB with this configuration.

[morgmart]

🤖 Automated code review

APPROVE. Corrected the completed review artifact for the exact three-dot comparison 37e706d...07279d8. Re-checking the current full diff and allowed anchors confirms that the three configuration-only changed files contain no publishable findings: the Cargo development profile preserves file-and-line backtraces while reducing debug-information cost and documents the full-debug override; the VS Code setting gives Rust Analyzer a separate target directory; and the ignore rules narrowly admit that shared setting. No graphical Berd interface, runtime user flow, accessibility behavior, localization, navigation or consent guard, async lifecycle, race behavior, design-system surface, or test contract changes in this comparison. No duplicate findings exist. Supplied GitHub evidence remains structurally valid for the exact base and head, records no local execution, and reports all 11 supplied check runs successful; required checks independently govern merge readiness.

Deterministic publication result: 0 blocking and 0 non-blocking inline finding(s) publishable; 0 duplicate(s) suppressed; 0 blocking screenshot-evidence requirement(s) in this review body.

Pending checks: 1 check(s) are not complete.

This approval reflects the completed code review only; merge readiness remains governed by the repository's required checks.