Fix/project import 413 error feedback

[zarch]

📌 Description

Problem: Importing a large project file (≥ 184 MB in the reported case) through the FUXA UI failed silently. The interface showed only a generic notification with Project save failed! with no indication of the actual cause, and the server logs contained no application-level error entry — only the raw HTTP access log line POST /api/project 413.

Three separate issues combined to produce this behaviour:

1. Server silent on 413: In server/api/index.js the Express error handler for entity.too.large returned the 413 response but never called runtime.logger.error(). The rejection was invisible in application logs.

2. Frontend discarded HTTP status: In client/src/app/_services/project.service.ts, the save() method had its own inline error handler that always showed the translated msg.project-save-error string, ignoring the HTTP status code entirely. The existing notifySaveError() helper already handled 401 and 413 correctly (surfacing the server message for 413, and a hint for status 0 / connection abort), but save() bypassed it.

3. Angular client could not be rebuilt: client/src/theme.scss used mat.m2-define-* functions and mat.$m2-* palette variables introduced in Angular Material 17, while the installed package is 16.2.13. This caused an "Undefined function" Sass compilation error that prevented any rebuild of the client bundle.

Changes:

• server/api/index.js: added runtime.logger.error() in the 413 error handler so the rejection appears in application logs alongside the HTTP access log entry.
• client/src/app/_services/project.service.ts: replaced the inline error handler in save() with a call to notifySaveError(err). Added a status === 0 branch in notifySaveError() for browsers that abort the connection mid-upload rather than receiving the 413 cleanly. Extended ServerSettings with apiMaxLength so the configured limit is available for that message.
• client/src/theme.scss: replaced all m2- prefixed Sass identifiers with their Angular Material 16 equivalents (mat.define-* / mat.$*-palette) to restore the ability to build the client. I keep these change in a separate commit because I do not know if you are in a transition phase from Angular Material 16 to Angular Material 17, but without this fix I was not able to test it locally. So in case let me know and I rebase it without this last commit.

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🧪 Type of Change

Please mark the relevant option:

• Bug fix
• New feature
• Refactoring
• Documentation
• Other

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🚫 Build Artifacts Check

Please confirm:

• I did NOT commit /client/dist
• I did NOT commit generated Angular build output
• Only source files are included

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🔍 Checklist

• Code follows project coding standards
• I tested my changes locally
• Documentation updated if required
• Issue opened (for major changes)

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📝 Additional Notes

The immediate trigger for the 413 is the default apiMaxLength of 100mb defined in server/api/index.js. To import a project larger than 100 MB without changing source code, add the following line to server/_appdata/settings.js:

apiMaxLength: '256mb',

Browser behaviour for large uploads is not standardised. Chrome typically receives the 413 response cleanly (the status === 413 branch fires and shows the server message verbatim). Firefox and some other clients abort the TCP connection before receiving the response (the status === 0 branch fires and shows the configured limit as a hint). Both paths now produce an actionable message instead of the generic fallback.

The server log will now show:

[ERR] api request rejected: The submitted content exceeds the maximum allowed size (100mb) 

The final result on the ui is:

[unocelli]

Hi @zarch Thanks for the PR. About theme.scss don't have to be change, I think you have to reinstall node_modules and build the client again