chore: release pympp@0.3.0

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0.3.0 (2026-02-23)

Minor Changes

• Added extensive test coverage for memo-based transfers, including unit tests for _match_transfer_calldata and _verify_transfer_logs with memo fields, integration tests for end-to-end charge flows with server-specified memos, and new test modules for body digest computation, error types, expires helpers, and keychain signature handling. (by @brendanryan, #70)
• Added 0x78 fee payer envelope encoding/decoding module with encode_fee_payer_envelope and decode_fee_payer_envelope functions. Updated ChargeIntent._cosign_as_fee_payer to use the new 0x78 wire format instead of 0x76, including sender address verification against the recovered signer. Exported USDC, PATH_USD, and default_currency_for_chain from the tempo package public API. (by @brendanryan, #70)
• Added chain-specific default currency selection: mainnet now defaults to USDC and testnet defaults to pathUSD. Exported USDC, PATH_USD, and default_currency_for_chain from the tempo package public API. Updated tests to reflect the new default currency behavior. (by @brendanryan, #70)

Patch Changes

• Added pyright, build, and twine as dev dependencies. Improved CI pipeline with separate lint, test, and package jobs, concurrency cancellation, coverage enforcement, and package validation. Fixed pyright type errors with type: ignore annotations and refactored ChargeIntent to use a _get_rpc_url() helper to safely unwrap the optional RPC URL. (by @brendanryan, #70)