Implemented the two missing reputation_bonus SDK methods

[vjuliaife]

Summary

Issue #426 asked for two SDK read methods wrapping reputation_bonus's existing get_config() and
get_reputation(address) view functions. Investigation confirmed the contract side
(contracts/reputation_bonus/src/lib.rs) already exposes both — the gap was entirely in the SDK.
I added the two wrappers to sdk/src/methods/reputation.ts, exported them (and their types) from
sdk/src/index.ts, and added tests to sdk/src/methods/reputation.test.ts, following the exact
conventions already used by the file's existing getReputation/submitReputationInvoice functions
(same simulation pattern, same ReputationContractError error mapping).

What changed:

• getReputationBonusConfig(server, contractId, networkPassphrase?) → { highRepThreshold,
  bonusBps, minDiscountRateBps }
• getReputationBonusReputation(server, contractId, address, networkPassphrase?) → {
  invoicesSubmitted, invoicesPaid, invoicesDefaulted, score }
• New types ReputationBonusConfig / ReputationBonusScore, exported from sdk/src/index.ts
• 10 new test cases (success, zeroed/unknown address, invalid address, simulation errors,
  contract error-code mapping)

Verified: full reputation.test.ts suite passes (23/23), no new TypeScript or lint errors
introduced (pre-existing unrelated errors in batch.ts/client.ts/nft.test.ts/insurance.test.ts
confirmed present on main too), 97.66% line coverage on the touched file, and an independent
review pass found no defects.

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PR body (paste as-is)

Summary

• Add getReputationBonusConfig() and getReputationBonusReputation(address) to the SDK,
  wrapping the reputation_bonus contract's existing get_config() and get_reputation(address)
  view functions.
• Add ReputationBonusConfig and ReputationBonusScore TypeScript types mirroring the Rust
  Config and ReputationScore structs.
• Add unit tests covering success, zeroed/unknown-address behavior, invalid-address rejection,
  and contract/RPC error paths.

Why

Frontend applications need to display reputation_bonus configuration (high_rep_threshold,
bonus_bps, min_discount_rate_bps) and per-address reputation scores, but the SDK didn't
expose these two existing view functions.

Details

• These are distinct from the existing getReputation() in the SDK, which targets the
  invoice_liquidity contract (a different contract with a different ReputationProfile shape
  that includes an address field). The new methods target reputation_bonus and mirror its
  ReputationScore shape exactly (no address field).
• Contract-side get_config/get_reputation already existed in
  contracts/reputation_bonus/src/lib.rs — no contract changes were needed.
• Read-only simulation calls follow the same pattern already used by sibling functions in
  sdk/src/methods/reputation.ts (dummy source account, SorobanRpc.Api.isSimulationError check,
  ReputationContractError.fromError mapping).

Testing

• npx vitest run src/methods/reputation.test.ts — 23/23 passing
• npx tsc --noEmit — no new type errors (pre-existing unrelated errors confirmed present on
  main)
• npx eslint src/methods/reputation.ts src/methods/reputation.test.ts src/index.ts — clean

Files changed

• sdk/src/methods/reputation.ts
• sdk/src/methods/reputation.test.ts
• sdk/src/index.ts

Closes #426