fix(android): stabilize lightserver connectivity, endpoint routing, a…

[finalis-core]

…nd send/read diagnostics

• normalize endpoint input to explorer base URL and derive RPC URL internally
  • migrate / inputs to explorer
  • strip accidental route inputs like
• enforce correct surface split
  • explorer reads via
  • broadcast via
• fix balance semantics in app UI
  • trust for displayed spendable balance
  • keep UTXO list for coin selection/send flow
• add strict UTXO parsing policy
  • accept
  • reject entries missing both instead of defaulting to zero
• improve endpoint health + diagnostics
  • add malformed-data classification
  • include resolved explorer URL, resolved RPC URL, and raw transport error
  • add per-endpoint probe diagnostics in saved endpoint cards
  • prioritize active-endpoint failure visibility over fallback noise
• improve resilience/performance
  • add short TTL caching + stale-if-error fallback for explorer reads
  • avoid redundant same-cycle address/status fetches
  • increase explorer HTTP connect/read timeouts to 15s
• fix stale UI state behavior
  • clear sticky endpoint-status messages correctly
  • preserve last good dashboard state on transient unavailable reads
• align labels/UX
  • rename “Finalized balance” -> “Spendable balance”
  • update endpoint input copy to avoid confusion
• housekeeping
  • remove deprecated manifest attributes in feature/data modules
  • update tests for endpoint normalization/fallback and diagnostics wiring