ci(rust): fix publish workflow crates.io 403 failure

[vrknetha]

Summary

• fix Rust publish workflow failure caused by crates.io data-access 403 on direct API calls
• replace direct crates.io HTTP checks with cargo info registry metadata lookups
• keep safety gates for unpublished versions and core-crate propagation before publishing CLI crate
• document release best practice updates in AGENTS guidance

Root Cause

Resolve next Rust version used raw curl against crates.io API endpoints, which returned HTTP 403 due crates.io data-access policy enforcement in GitHub Actions.

Validation

• verified cargo info based version lookup locally
• verified unpublished-version checks for clawdentity-core and clawdentity-cli
• verified propagation-check command path for existing versions
• pre-push affected checks ran during git push

[vrknetha]

Fix addresses the failure from run https://github.com/vrknetha/clawdentity/actions/runs/22348267698/job/64668417630 by removing direct crates.io API calls that returned 403 under data-access policy.\n\nWorkflow now uses cargo info metadata/index lookups for:\n- current version resolution\n- unpublished target-version checks\n- clawdentity-core propagation wait before publishing clawdentity-cli\n\nThis preserves version automation and publish safety without raw crates HTTP calls.

[vrknetha]

Applied follow-up fix for the latest failure in Resolve current and next crate version:\n\n- force CARGO_TERM_COLOR=never for all cargo info checks\n- strip ANSI escape codes before parsing version:\n\nThis addresses colorized output from Actions causing the parser to return an empty version. Commit: a3b8a9a.