feat: enable isolatedModules

[marcj]

• Add tsconfig.base.json with shared compiler options
• Enable isolatedModules for compatibility with esbuild/swc/Babel
• Convert const enums to regular enums (required for isolatedModules)
• Remove emitDecoratorMetadata (unused, Deepkit uses type-compiler)
• All package tsconfigs now extend the base config

BREAKING CHANGE: const enums converted to regular enums in:

• MappedModifier (type-spec)
• BinaryBigIntType (type)
• BrokerType (broker)
• RpcMessageRouteType (rpc)
• AuthMechanism (mongo)

[Copilot]

Pull request overview

This PR establishes a centralized TypeScript configuration pattern by introducing tsconfig.base.json with shared compiler options, most notably enabling isolatedModules for compatibility with modern fast transpilers (esbuild, swc, Babel). All package-level tsconfig.json files now extend this base configuration, eliminating duplication across 50+ packages.

Key changes:

• Created tsconfig.base.json with shared TypeScript compiler options including isolatedModules: true
• Converted all const enum declarations to regular enum (required for isolatedModules)
• Removed emitDecoratorMetadata from all configs (unused since Deepkit uses type-compiler)

Reviewed changes

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Show a summary per file

File	Description
tsconfig.base.json	New centralized TypeScript configuration with shared compiler options and isolatedModules enabled
packages/*/tsconfig.json	All package configs now extend the base config, removing duplicated options
packages/type/src/reflection/type.ts	Converted BinaryBigIntType from const enum to regular enum
packages/type-spec/src/type.ts	Converted MappedModifier from const enum to regular enum
packages/rpc/src/protocol.ts	Converted RpcMessageRouteType from const enum to regular enum
packages/broker/src/model.ts	Converted BrokerType from const enum to regular enum
packages/mongo/src/client/command/handshake.ts	Converted AuthMechanism from const enum to regular enum

Comments suppressed due to low confidence (4)

packages/orm-browser-gui/tsconfig.json:28

• These compiler options (forceConsistentCasingInFileNames, strict, noFallthroughCasesInSwitch, sourceMap, experimentalDecorators, esModuleInterop, moduleResolution, skipLibCheck) are redundant as they're already defined in tsconfig.base.json. Consider removing them to avoid duplication and potential inconsistencies.
  packages/framework-debug-gui/tsconfig.json:27
• These compiler options (forceConsistentCasingInFileNames, strict, noFallthroughCasesInSwitch, sourceMap, experimentalDecorators, esModuleInterop, moduleResolution, skipLibCheck) are redundant as they're already defined in tsconfig.base.json. Consider removing them to avoid duplication and potential inconsistencies.

    "forceConsistentCasingInFileNames": true,
    "allowSyntheticDefaultImports": true,
    "strict": true,
    "noFallthroughCasesInSwitch": true,
    "sourceMap": true,
    "skipLibCheck": true,
    "declaration": false,
    "composite": false,
    "downlevelIteration": true,
    "experimentalDecorators": true,
    "moduleResolution": "node",
    "importHelpers": true,
    "target": "es2022",
    "module": "ES2022",
    "useDefineForClassFields": false,
    "types": [
      "dagre",
      "file-saver",
      "jasmine",
      "marked"
    ]

packages/api-console-gui/tsconfig.json:25

• These compiler options (forceConsistentCasingInFileNames, strict, noFallthroughCasesInSwitch, sourceMap, experimentalDecorators, esModuleInterop, moduleResolution, skipLibCheck) are redundant as they're already defined in tsconfig.base.json. Consider removing them to avoid duplication and potential inconsistencies.

    "forceConsistentCasingInFileNames": true,
    "strict": true,
    "noFallthroughCasesInSwitch": true,
    "allowSyntheticDefaultImports": true,
    "sourceMap": true,
    "skipLibCheck": true,
    "declaration": false,
    "composite": false,
    "downlevelIteration": true,
    "experimentalDecorators": true,
    "moduleResolution": "node",
    "importHelpers": true,
    "target": "es2022",
    "module": "ES2022",
    "useDefineForClassFields": false,
    "types": [
      "jasmine",
      "marked"
    ]

packages/desktop-ui/tsconfig.json:28

• These compiler options (moduleResolution, experimentalDecorators, downlevelIteration, sourceMap, strict, esModuleInterop, skipLibCheck) are redundant as they're already defined in tsconfig.base.json. Consider removing them to avoid duplication and potential inconsistencies.

    "moduleResolution": "node",
    "experimentalDecorators": true,
    "downlevelIteration": true,
    "sourceMap": true,
    "strict": true,
    "target": "es2022",
    "useDefineForClassFields": false,
    "noImplicitAny": true,
    "esModuleInterop": true,
    "preserveSymlinks": true,
    "types": [
      "fs-extra",
      "node"
    ],
    "paths": {
      "angular-desktop-ui": [
        "dist/"
      ]
    },
    "skipLibCheck": true

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