[witbrock]

What changed

• Keep uploaded-file state outside the chat composer and expose persistent progress/attachment status.
• Scope in-flight upload guards, progress, completion UI, and pending attachment bindings to the originating conversation.
• Coalesce repeated in-flight actions without creating duplicate upload concepts or transcript cards, while allowing another conversation to upload independently.
• Mark tables mechanically derived from inline Markdown as inline_primary, with an explicit source element and line span.
• Render explicit structured tables as augmenting cards, but suppress a derived card only when source ownership and the live inline presentation are both proven; otherwise fail open so content cannot disappear.
• Preserve raw/text view faithfully.

Root cause

Upload UI state was page-global even though durable attachment bindings were conversation-scoped. Separately, the display contract did not identify which renderer owned a table derived from inline response content, so both the Markdown renderer and display-element renderer presented it.

User impact

Uploads no longer rewrite the prompt draft, repeat actions no longer duplicate work, conversation switches cannot leak upload state into another chat, and Markdown tables appear once while genuinely explicit structured tables remain available.

Validation

• 57 passed: tests/backend/test_display_elements_service.py
• 19 passed: attachment binding, display ownership, and Markdown rendering Jest suites
• Ruff, ESLint, Node syntax, and git diff --check
• Live isolated server health on port 5014 and browser inspection of the actual composer/status surface; automated Chrome file selection was unavailable because file-URL access is disabled, so slow-upload and cross-session behaviour is covered by the focused Jest paths.

[Copilot]

Pull request overview

This PR fixes two user-facing chat issues in Von’s web UI: (1) attachment/upload UI state incorrectly leaking across conversations and rewriting prompt drafts, and (2) Markdown-derived tables being rendered twice due to unclear ownership between the Markdown renderer and the display-elements renderer.

Changes:

• Introduces conversation-scoped upload state and a persistent attachment/progress status region in the chat composer.
• Adds presentation.mode (notably inline_primary) and source-span metadata for Markdown-derived tables, plus renderer-side suppression logic to prevent duplicate table rendering while failing open when ownership can’t be proven.
• Expands frontend and backend test coverage around attachment binding, upload coalescing, and display-element table ownership/validation.

Reviewed changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
tests/frontend/chatTabMarkdownRender.test.js	Ensures Markdown tables don’t duplicate when display_elements includes inline-primary tables.
tests/frontend/chatDisplayElementOwnership.test.js	Adds coverage for table ownership suppression vs augment rendering and raw-view fidelity.
tests/frontend/chatAttachmentWorkflowInput.test.js	Adds tests for persistent attachment status, upload coalescing, and per-conversation upload isolation.
tests/backend/test_display_elements_service.py	Adds backend tests for source-span correctness and validation around table presentation metadata.
src/frontend/web/von_interface/templates/chat_tab.html	Adds a dedicated attachment status region in the composer and moves status output into it.
src/frontend/web/von_interface/static/styles.css	Styles the new attachment status region and pending-attachment “pill” UI.
src/frontend/web/von_interface/static/js/chatTab.js	Implements table presentation normalisation/suppression and conversation-scoped upload state + UI rendering.
src/backend/services/display_elements_service.py	Preserves fence line positions for source spans and adds table presentation validation + emission.