Improve test coverage for critical components to >80%

[prdlk]

Requirements

• Must achieve >80% coverage for critical security components (ante handlers, authentication, authorization)
• Must achieve >70% coverage for all keeper implementations
• Must achieve >60% coverage for non-generated type definitions
• Must implement comprehensive integration tests for critical user flows
• Must establish continuous coverage monitoring in CI/CD pipeline

Context

Current Coverage Status

Overall test coverage is currently at 3.4%, which is critically low. Key areas requiring immediate attention:

Critical Components with Poor Coverage

• app/ante: 8.4% - Transaction ante handlers (security critical)
• internal/ucan: 4.5% - User-Controlled Authorization Networks
• internal/bridge/handlers: 1.4% - Bridge request handlers
• x/did/types: 1.2% - DID type definitions
• x/dwn/types: 0.5% - DWN type definitions
• x/svc/types: 0.9% - Service type definitions

Components with Zero Coverage

• app/commands - CLI commands
• internal/ipfs - IPFS client operations
• x/did/client/server - DID server implementation
• WebAuthn sub-packages (cbor, revoke)

Affected Files

High Priority (Security Critical)

• app/ante/ante.go
• app/ante/webauthn_decorator.go
• internal/ucan/validator.go
• internal/webauthn/revoke/revocation.go

Keeper Implementations

• x/did/keeper/msg_server.go
• x/dwn/keeper/msg_server.go
• x/svc/keeper/msg_server.go

Type Definitions

• x/did/types/*.go (excluding .pb.go files)
• x/dwn/types/*.go (excluding .pb.go files)
• x/svc/types/*.go (excluding .pb.go files)

Bridge and Integration

• internal/bridge/handlers/*.go
• internal/bridge/tasks/*.go
• internal/ipfs/client.go

Relevant Documentation

• Go Testing Best Practices
• Cosmos SDK Testing Guide
• Table-Driven Tests in Go

Acceptance Criteria

Security Components (>80% coverage)

• Ante handler tests covering all decorator chains and edge cases
• WebAuthn decorator tests with gasless transaction scenarios
• UCAN validation tests with permission matrix coverage
• Revocation mechanism tests with timing attack prevention

Keeper Tests (>70% coverage)

• Message server tests for all RPC methods in x/did
• Message server tests for all RPC methods in x/dwn
• Message server tests for all RPC methods in x/svc
• Query server tests with pagination and error cases
• Genesis import/export round-trip tests

Type Definition Tests (>60% coverage)

• Validation tests for all custom types
• Marshaling/unmarshaling tests for complex structures
• Edge case tests for type conversions
• Default value and nil handling tests

Integration Tests

• End-to-end WebAuthn registration flow
• DID document creation and resolution
• DWN record encryption/decryption cycle
• Vault creation and IPFS persistence
• Service registration and verification flow

Infrastructure

• Coverage reports integrated into CI pipeline
• Coverage badges in README
• Failing builds when coverage drops below thresholds
• Test coverage trend tracking

Performance Tests

• Benchmark tests for cryptographic operations
• Load tests for keeper operations
• Memory leak detection tests
• Concurrent access stress tests