Propagate dispatch idempotency to composite effects

[rita-aga]

Summary

• pass the generated parent dispatch idempotency into composite WASM sub-write application
• preserve caller-supplied idempotency for retries
• leave adapter callbacks on their existing idempotency behavior so same-entity callbacks are not deduped
• prevent repeated composite app version updates from reusing sub-write idempotency keys

Tests

• cargo fmt --check
• cargo test -p temper-server --test adapter_dispatch
• cargo test -p temper-server composite_wasm_result
• git diff --check

Safety

No database reset, wipe, truncate, restore, replacement, or manual row deletion.