TokenLink v0.2.3: quota dial and Cost Center

[phantom5125]

Summary

• redesign the C152 first page around the TokenLink quota arc and time-proportional pace
• add the Mac Cost Center with Today / Week / Month estimates and calculation provenance
• align Codex API-equivalent costs with request-level community accounting and reviewed GPT-5.6 prices
• preserve multi-plan Quota and session-focus behavior while improving the small-size Mac icon
• prepare v0.2.3-rc.1 release notes and an ad-hoc-signed GitHub prerelease path; stable tags still require Developer ID signing and notarization

Validation

• 265 Swift tests
• strict Swift format lint
• privacy scan
• resource gate: 79,200,256-byte max RSS, 9.84 s, 6,688,040-byte release executable
• C152 PlatformIO build and simulator/native tests
• firmware package checksums
• Universal 2 TokenLink-0.2.3.dmg build, mount, resource, signature, and architecture verification

Review focus

Please use the v0.2.3-rc.1 assets for hands-on review before merge. This PR supersedes the narrower provider-costs PR #2.