Improve importing

[antfu]

Changes

Add importCache

To reuse the loaded files. (also hackable)

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Nested import supported.

The current source file path will be included in importPaths now. This allows import from nested structures. Which is also very useful for 3rd-party modules.

For example, it makes importing 草部.wy from 讀經.wy possible.

├── 讀經.wy
└── 四庫全書
        ├── 本草綱目
        |       ├── 序.wy
        |       └── 草部.wy
        └── 序.wy

For more details, check out test/import.test.js and test/fixture/nest-import

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Add importContext

The reader will search for the context first before searching fs/web resources. This is to replace the custom reader. The reader option will NOT exposing now.

IDE2 can also import user scripts now:

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Test suits included

[LingDong-]

Great! Thanks a lot!