✨(frontend) warn the user when trying to upload a file size that exceeds the limit

[magopian]

Fixes #2460

Purpose

Currently the message displayed to the user conveys no information on the error that occured when uploading a big file which size exceeds the limit.

Proposal

• expose the DOCUMENT_IMAGE_MAX_SIZE configuration through the /api/v1.0/config endpoint
• check the size of the file before trying to upload it
• optional: also display a nice error message to the user if the production nginx server answers with a HTTP 413 message

External contributions

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[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Repository UI

Review profile: ASSERTIVE

Plan: Pro

Run ID: d2545aa8-8052-4acf-b19c-3e149bff8b7b

📥 Commits

Reviewing files that changed from the base of the PR and between 6d0d6f7 and 6822be9.

📒 Files selected for processing (6)

• CHANGELOG.md
• src/frontend/apps/e2e/__tests__/app-impress/doc-editor-upload.spec.ts
• src/frontend/apps/e2e/__tests__/app-impress/utils-common.ts
• src/frontend/apps/impress/src/features/docs/doc-editor/components/BlockNoteEditor.tsx
• src/frontend/apps/impress/src/features/docs/doc-editor/hook/__tests__/useUploadFile.test.tsx
• src/frontend/apps/impress/src/features/docs/doc-editor/hook/useUploadFile.tsx

---

Walkthrough

The configuration API and frontend types now expose DOCUMENT_IMAGE_MAX_SIZE. useUploadFile validates files before upload, reports translated size errors, and preserves backend error behavior. The document editor blocks oversized drops and pastes and refreshes the error display for retries. API error parsing now tolerates non-JSON responses. Unit and Playwright tests cover configuration, validation, error handling, and repeated oversized uploads.

Estimated code review effort: 3 (Moderate) | ~20 minutes

Suggested reviewers: antolc

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly summarizes the main change: warning users when uploads exceed the size limit.
Description check	✅ Passed	The description is directly related to the PR and matches the implemented upload-size UX improvements.
Linked Issues check	✅ Passed	The changes satisfy #2460 by exposing the size config, validating file size before upload, and handling 413 errors gracefully.
Out of Scope Changes check	✅ Passed	The diff stays focused on oversized upload handling, related config wiring, and tests with no unrelated scope creep.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

✨ Finishing Touches

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• Create PR with unit tests

---

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[coderabbitai]

Actionable comments posted: 2

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In
`@src/frontend/apps/impress/src/features/docs/doc-editor/components/BlockNoteEditor.tsx`:
- Around line 267-286: Update the existing pasteHandler to validate clipboard
files with checkFileSize before invoking defaultPasteHandler. Return early when
validation fails so oversized pasted files cannot create stuck loading blocks,
while preserving the existing thread refresh and default paste behavior for
valid files.

In
`@src/frontend/apps/impress/src/features/docs/doc-editor/hook/useUploadFile.tsx`:
- Around line 66-68: Update the errorAttachment assignment in the upload hook to
prioritize sizeError over the existing errorAttachment, while preserving the
current isErrorAttachment and sizeErrorKey behavior. This ensures a newly
detected file-size error is returned instead of a stale React Query upload
error.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Repository UI

Review profile: ASSERTIVE

Plan: Pro

Run ID: 0b0a87c2-f434-410c-a8a5-aeb016fa4b2c

📥 Commits

Reviewing files that changed from the base of the PR and between 8d2dd5b and 6d0d6f7.

📒 Files selected for processing (11)

• CHANGELOG.md
• src/backend/core/api/viewsets.py
• src/backend/core/tests/test_api_config.py
• src/frontend/apps/e2e/__tests__/app-impress/doc-editor-upload.spec.ts
• src/frontend/apps/e2e/__tests__/app-impress/utils-common.ts
• src/frontend/apps/impress/src/api/__tests__/utils.test.ts
• src/frontend/apps/impress/src/api/utils.ts
• src/frontend/apps/impress/src/core/config/api/useConfig.tsx
• src/frontend/apps/impress/src/features/docs/doc-editor/components/BlockNoteEditor.tsx
• src/frontend/apps/impress/src/features/docs/doc-editor/hook/__tests__/useUploadFile.test.tsx
• src/frontend/apps/impress/src/features/docs/doc-editor/hook/useUploadFile.tsx