Indexing strategy: on-chain enumeration vs events

[greatest0fallt1me]

Description

Document that full enumeration of streams is indexer responsibility; if adding streams_for_payer map, spec cost and caps.

Requirements and context

• Prefer events + indexer.
• Optional capped view follow-up.

Suggested execution

• Fork the repository and create a branch (example below).
• Implement the changes in the StreamPay-Contracts Soroban crate (streampay-contracts).
• Keep the contract secure, tested, and documented; prefer small, reviewable diffs.

git checkout -b docs/indexer-vs-onchain-list

Implementation targets

• docs/indexing.md.

Tests and validation

• N/A.

• Run cargo test in StreamPay-Contracts.

• Cover edge cases; capture test output and short security notes in the PR description.

Guidelines

• Target minimum 95% test coverage for touched contract code (or justify gaps explicitly).
• Clear documentation (rustdoc / project docs as specified).
• Timeframe: 96 hours from assignment.

Example commit message

docs(contracts): indexing strategy for stream lists