docs: reconcile provider work surface

[tttboy123]

Summary

• close source Draft PRs fix: reconcile Codex local token history #36-feat: add measured performance budgets #47 after their hardened commits landed through integration: assemble OpenUsage Bar 0.6 RC candidate #48
• close completed Provider issues Validate Cursor capacity, PATH, timeout, and fallback semantics #22, Validate Kiro AWS quota and read-only Keychain access #23, and Validate Claude Code, OpenCode, and local-tool coverage #25-Publish the Provider Adapter Kit and conformance example #29 with implementation and verification evidence
• keep external account gates Reconcile Codex local-session Token coverage with account totals #19-Validate StepFun regional quota and session isolation #21 and Validate OpenAI Organization usage and billed-cost pagination #24 open
• update the canonical work queue to match GitHub and current provider evidence

Verification

• 116 targeted Provider catalog, capability, Cursor/OpenUsage, Kiro, Moonshot, Adapter Kit, and conformance tests passed
• release metadata: release_metadata_ok version=0.6.0 build=9
• full-history release secret scan: 0 matches
• git diff --check passed

Boundary

• documentation-only repository change
• no Provider credentials, account data, release tags, or published assets changed
• no external account evidence was inferred from fixtures