fix(indexer): match resolutionParser to the real on-chain event shape

[melopaul]

Summary

• resolutionParser's topic constant ("market_resolved") never matched a real event, for the same root cause as marketCreatedParser (see Wire market_created parser into ingestion loop #590): Soroban's #[contractevent] macro snake-cases the full struct name including its Event suffix, so MarketResolvedEvent (contracts/market/src/events.rs) actually publishes under market_resolved_event — confirmed directly against the contract's own test_emit_market_resolved unit test. Every market_resolved event was being silently skipped in production.
• The "canonical on-chain tuple" shape the parser targeted was also a guess that doesn't match the real event. MarketResolvedEvent carries market_id as topics[1] (u32, a #[topic] field) with only { outcome: bool, resolved_at: u64 } in the value — not a 3-element tuple packed into the value. parseResolutionPayload now reads market_id from the topic for this shape, which matches this issue's "u32 bool u64 payload" description precisely: a u32 topic plus bool/u64 value fields, not a single tuple.
• The pre-existing legacy ScvVec 3-tuple and legacy ScvMap (with market_id/outcome/oracle all in the value) code paths are left intact for backward compatibility. Shape detection now branches on whether the value is an array, a map containing market_id (legacy), or a map without it (the real on-chain shape).

Why

Same class of bug as #590: the backend assumed a topic-naming convention that doesn't match what Soroban's #[contractevent] macro actually generates, and the payload shape was guessed rather than read from the contract source.

Test plan

• Updated apps/indexer/src/resolutionParser.test.ts with the real topic and new real-shape test vectors (topic-derived market_id, missing-topic error case), alongside the existing legacy tuple/map coverage.
• Fixed apps/indexer/src/ingestion.test.ts's RESOLUTION_TOPIC fixture constant to the real topic so the end-to-end ingestion test still exercises a matching event.
• npx vitest run apps/indexer/src — all pass except 3 pre-existing, unrelated failures already present on dev (collateralDepositedParser.test.ts, storage.test.ts).
• Updated docs/indexer-event-mapping.md and apps/indexer/fixtures/contract-event-vectors.json to document the corrected topic and payload shape.

Closes #589