Address review critical issues

- Fix test coverage to 70% (matching graduation criteria)
- Remove detailed directory structure
- Add toolhive-registry to Problem Statement repo list

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: JAORMX

rfcs/THV-0032-toolhive-core-shared-library.md

@@ -15,6 +15,7 @@ This RFC proposes creating a shared Go library (`toolhive-core`) to provide stab
 
 The ToolHive ecosystem spans multiple Go repositories:
 - **toolhive** - Core runtime, CLI, operator, proxy-runner, virtual MCP
+- **toolhive-registry** - Registry data and CLI tools
 - **toolhive-registry-server** - Registry API server
 - **dockyard** - Container packaging for MCP servers
 
@@ -180,40 +181,6 @@ These packages meet all graduation criteria (zero ToolHive-specific coupling, we
 
 > **Note**: All packages start as Beta in v0.x releases. Once the library reaches v1.0.0, packages meeting all graduation criteria will be promoted to Stable.
 
-**Proposed `toolhive-core` structure:**
-
-```
-toolhive-core/
-├── go.mod
-├── go.sum
-├── README.md
-├── CHANGELOG.md
-├── errors/
-│   ├── errors.go        # CodedError, WithCode, Code()
-│   ├── errors_test.go
-│   └── doc.go
-├── oauth/
-│   ├── oauth.go         # AuthorizationServerMetadata, OIDCDiscoveryDocument
-│   ├── oauth_test.go
-│   └── doc.go
-├── env/
-│   ├── env.go           # Reader interface, OSReader
-│   ├── env_test.go
-│   └── doc.go
-├── permissions/
-│   ├── profile.go       # Profile, NetworkPermissions, MountDeclaration
-│   ├── profile_test.go
-│   └── doc.go
-├── validation/
-│   ├── validation.go    # HTTP header, URI, group name validators
-│   ├── validation_test.go
-│   └── doc.go
-└── versions/
-    ├── version.go       # VersionInfo, GetUserAgent
-    ├── version_test.go
-    └── doc.go
-```
-
 #### Tier 2: Minor Refactoring Required
 
 These packages have solid implementations but need minor changes to remove ToolHive-specific coupling:
@@ -315,7 +282,7 @@ These packages are too coupled to ToolHive internals:
 
 ### Unit Tests
 
-- All packages must have ≥80% coverage
+- All packages must have ≥70% coverage
 - Table-driven tests for validation functions
 - Mock-based tests for interface implementations