Network RPC Dependency and Trust Boundaries

WAproxy depends on external blockchain RPC nodes
for transaction broadcast and balance queries.

RPC is a dependency, not an authority.

------------------------------------------------------------
RPC ROLE
------------------------------------------------------------

RPC provides:

- raw transaction broadcast
- UTXO state queries
- mempool visibility
- block confirmation data

RPC does NOT define:

- protocol fee logic
- idempotency rules
- safety margin enforcement
- execution policy

------------------------------------------------------------
TRUST BOUNDARY
------------------------------------------------------------

WAproxy must treat RPC responses as:

- necessary
- but not absolute economic authority

All execution logic must be validated
before RPC interaction.

------------------------------------------------------------
FAILURE HANDLING
------------------------------------------------------------

If RPC:

- is unavailable
- times out
- returns inconsistent data

WAproxy must:

- reject execution safely
- avoid partial state mutation
- allow deterministic retry

------------------------------------------------------------
RPC CREDENTIAL ISOLATION
------------------------------------------------------------

RPC credentials must:

- be stored in environment variables
- never be exposed via API
- never be logged in plain text
- be isolated per coin

------------------------------------------------------------
CHAIN SEPARATION
------------------------------------------------------------

Each coin defines:

- RPC_HOST_MAIN
- RPC_HOST_TEST

Execution must respect selected network.
Cross-network broadcast is forbidden.

------------------------------------------------------------
DEPENDENCY DISCIPLINE
------------------------------------------------------------

WAproxy does not attempt to:

- replace blockchain node validation
- modify raw consensus rules
- override mempool acceptance policy

It operates within blockchain-defined rules.

------------------------------------------------------------
ARCHITECTURAL STATEMENT
------------------------------------------------------------

Blockchain RPC is a transport dependency.

Execution discipline belongs to WAproxy.
Consensus belongs to the chain.