Phase out client.tsp separate entrypoint

[timotheeguerin]

Phase 1: Import client.tsp from main.tsp

• a. First services that need no changes apart from adding import "./client.tsp"
  • Phase 1.a: Import client.tsp from main.tsp for safe services azure-rest-api-specs#43749
  • https://github.com/Azure/azure-rest-api-specs-pr/pull/28819
• b. Second services that might need simple tweaking (adding !autorest to scope)
  • Phase 1.b: Scope TCGC decorators and import client.tsp for 31 additional services azure-rest-api-specs#43751
  • https://github.com/Azure/azure-rest-api-specs-pr/pull/28820
  • Import client.tsp from main.tsp for services with no swagger impact azure-rest-api-specs#44009
• c. more complex services
  • Import client.tsp from main.tsp for deploymentStacks, policy, and search (@scope support) azure-rest-api-specs#44027

specification/applink/AppLink.Management
specification/edge/Microsoft.Edge.DisconnectedOperations.Management
specification/frontdoor/resource-manager/Microsoft.Network/FrontDoor
specification/migrate/resource-manager/Microsoft.Migrate/Waves
specification/monitoringservice/resource-manager/Microsoft.Monitor/Agents
specification/napster/Napster.CompanionAPI.Management
specification/programenrollment/resource-manager/Microsoft.ProgramEnrollment/ProgramEnrollment
specification/purviewdatagovernance/data-plane/DataAccess
specification/relationships/Relationships.Management
specification/resources/resource-manager/Microsoft.Authorization/policy
specification/resources/resource-manager/Microsoft.Resources/deploymentStacks
specification/search/resource-manager/Microsoft.Search/Search
specification/storagecache/resource-manager/Microsoft.StorageCache/StorageCache

Phase 2: Enforce client.tsp import

• Add tsv validation to make sure client.tsp is imported Add ClientTspImport validation rule to TSV azure-rest-api-specs#43762

Phase 3: Update tooling

• Linting rule to prevent bad pattern in client.tsp Add linter rule to prevent redefining the service namespace in client.tsp #4652
• Update tsp client and logic in emitters
• cleanup/fix test in typespec-azure reproing the structure
• Documentation
  • docs: reference new spec structure where main.tsp imports client.tsp #4677
  • Should we relax restriction about tcgc needing to be imported in client.tsp only??

Phase 4: Cleanup

• Remove import main.tsp from client.tsp