docs: strengthen Standby institutional and economic framing

[garykocsis]

Summary

Strengthens Standby's judge-facing and institutional presentation after completion of F10 without changing protocol semantics, implementation behavior, or accepted verification results.

This update makes the economic purpose of the protocol more explicit: who future execution capacity may be useful for, why an institution may prefer protected capacity over pre-positioning the destination asset, why Uniswap v4 is the enforcement boundary, what economic constraint supporting liquidity accepts, and what remains outside the reference implementation.

Changes

• add target-user and institutional-use-case framing
• add an illustrative tokenized-Treasury / future-USDC settlement scenario
• explain that commitments are bounded in both quantity and time
• preserve the distinction between fulfillment and expiration, including partial fulfillment followed by expiry
• explain why Standby enforcement belongs at the Uniswap v4 state-transition boundary
• clarify that S >= O requires no excess reserve margin
• describe the economic roles of the capacity purchaser and supporting liquidity
• distinguish a potential future capacity premium from actual AMM input settlement at exercise
• explicitly leave capacity pricing, LP attribution, premium distribution, and market design outside the reference implementation
• explain the external EligibilityRegistry permissioning boundary
• clarify that Standby does not currently integrate with Uniswap Permissioned Pools
• add a bounded Path to Production covering economics, permissioning, deployment, security, operations, and market validation
• surface the accepted F10 verification evidence in the README

Preserved Boundaries

• no production code changes
• no test changes
• no protocol-semantic changes
• no canonical artifact changes
• no project-status changes
• canonical A1–A4 acceptance evidence unchanged
• both existing Mermaid diagrams preserved byte-identically
• F10 remains COMPLETE
• G10 remains CLOSED / PASS
• F9T remains optional and off the critical path

Verification

• git diff --check clean
• both Mermaid blocks verified byte-identical to HEAD
• README relative links verified
• canonical demo fixture quantities preserved
• accepted 590-test evidence reconfirmed
• README independently reviewed for semantic consistency and economic/permissioning overclaiming

Session Evidence

Includes the Session 18 prompt, implementation log, semantic-correction follow-up, and ChatGPT retrospective reasoning record.