fix(form/Editor): only use the bundled monaco editor

[SkyeYoung]

Please answer these questions before submitting a pull request, or your PR will get closed.

Why submit this pull request?

• Bugfix
• New feature provided
• Improve performance
• Backport patches

What changes will this PR take into?

Ensure that only the bundled Monaco is used.

OLD	NEW

Related issues

fix/resolve #3167

Checklist:

• Did you explain what problem does this PR solve? Or what new features have been added?
• Have you added corresponding test cases?
• Have you modified the corresponding document?
• Is this PR backward compatible? If it is not backward compatible, please discuss on the mailing list first

[Copilot]

Pull Request Overview

This PR fixes an issue with the Monaco Editor integration by ensuring only the bundled Monaco Editor is used instead of potentially mixing different versions. The changes remove the dynamic Monaco setup and implement a static initialization approach.

• Removes dynamic Monaco setup function and implements static initialization
• Updates import statements to use the bundled Monaco editor directly
• Removes the beforeMount callback that was causing potential version conflicts

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[bzp2010]

Will this make the build artifacts larger?

[SkyeYoung]

@bzp2010 I tried packing it up and found that there are indeed many unused ones that are not useful, so let me see how to deal with it.(Although they are not bigger than antd)

[SkyeYoung]

@bzp2010 I've added manual chunks to determine the size occupied by Monaco.

// old
dist/assets/apisix-logo-HMKlWzJ1.svg               0.81 kB │ gzip:   0.39 kB
dist/index.html                                    0.86 kB │ gzip:   0.41 kB
dist/assets/codicon-DCmgc-ay.ttf                  80.34 kB
dist/assets/editor.worker-oRlJJsnX.js            234.39 kB
dist/assets/json.worker-BnUULff4.js              366.81 kB
dist/assets/monaco-editor-vendor-C37UlGMP.css    133.05 kB │ gzip:  21.19 kB
...
dist/assets/react-vendor-DoC2WAmd.js              12.45 kB │ gzip:   4.41 kB
dist/assets/monaco-editor-vendor-vNTR5Nef.js      16.29 kB │ gzip:   5.75 kB
dist/assets/index-F8cMEI97.js                    781.75 kB │ gzip: 240.26 kB
dist/assets/antd-vendor-6KqauUkE.js            1,910.39 kB │ gzip: 602.56 kB
total: 3.8M    dist

// new
dist/assets/apisix-logo-HMKlWzJ1.svg               0.81 kB │ gzip:   0.39 kB
dist/index.html                                    0.86 kB │ gzip:   0.40 kB
dist/assets/codicon-DCmgc-ay.ttf                  80.34 kB
dist/assets/editor.worker-oRlJJsnX.js            234.39 kB
dist/assets/json.worker-BnUULff4.js              366.81 kB
dist/assets/monaco-editor-vendor-CUMOsoFg.css    133.05 kB │ gzip:  21.21 kB
...
dist/assets/react-vendor-DoC2WAmd.js              12.45 kB │ gzip:   4.41 kB
dist/assets/jsonMode-BmdQK4IJ.js                  41.83 kB │ gzip:  12.15 kB
dist/assets/index-D_R-G-sa.js                    781.70 kB │ gzip: 240.25 kB
dist/assets/antd-vendor-C01oSD3T.js            1,910.39 kB │ gzip: 602.57 kB
dist/assets/monaco-editor-vendor-DU3RmTXG.js   3,280.78 kB │ gzip: 846.12 kB
total: 7.0M    dist

We will find that the size of the Monaco editor starts from (gzip: 5.75 kB) to (gzip: 846.12 kB).

But I think the Monaco editor part is necessary for now. As for the size, there might be ways to further reduce the size, but I don't have time to research further at the moment.(We might as well consider removing parts of antd.)

Manual chunks will optimize the first screen loading to some extent, and I've decided to keep it in this PR.