* perf: cache KaTeX module import as singleton across all renderer instances
KatexRenderer.svelte dynamically imports katex, mhchem, and the CSS on every component mount. When a message contains multiple math expressions, this triggers redundant module resolution for each one. Move the import promise to a module-level singleton using Svelte's context='module' script block so it loads once and is shared across all KatexRenderer instances.
* Update KatexRenderer.svelte
ResponseMessage compared the entire message object via JSON.stringify on every reactive tick to detect changes. During streaming, content changes on every token, making the two O(content_length) JSON.stringify calls always return different results — pure wasted work. Add a fast O(1) comparison on content and done fields first. When either differs (the common streaming case), skip straight to cloning. Only fall through to the expensive JSON.stringify comparison for infrequent changes like sources, annotations, or status updates.
fix: model fallback routing for all model types and default model selection
Backend: When ENABLE_CUSTOM_MODEL_FALLBACK is active and a custom model's
base model is unavailable, the fallback now swaps the model and form data
to the configured default model directly. This ensures routing uses the
fallback model's type (pipe, Ollama, or OpenAI) instead of the original
model's type, which previously caused "Model not found" errors when the
fallback was a different backend type.
Frontend: Fixed default model selection in new chat initialization where
the admin-configured default models were always overwritten by the first
available model. The first-available fallback now only triggers when the
configured defaults don't resolve to valid available models.
This commit adds aria-labels to the text inputs and textareas that previously lacked them, applies role=switch to inputs, and adds accessible titles to floating quick actions.
fix: reset taskIds and messageQueue on new chat
Fixes a bug where clicking "New Chat" after sending a message would
silently drop subsequent messages. The initNewChat function reset most
chat state but did not clear taskIds or messageQueue, causing
submitPrompt to queue messages indefinitely instead of sending them.
- Replace incorrect aria-roledescription='model-item' with role='option' and aria-selected on ModelItem.svelte. The previous attribute was not a valid ARIA role description and provided no useful information to screen readers.
- Add contextual aria-label to each model item button (e.g. 'Select GPT-4 model') instead of just the raw model name, making the action clear to screen reader users.
- Add role='listbox' and aria-label='Available models' to the scrollable model list container in Selector.svelte so screen readers announce the container's purpose and navigate items correctly.
- Make the model selector trigger button's aria-label dynamic: it now announces 'Selected model: GPT-4' when a model is selected, falling back to 'Select a model' when nothing is selected.
- Add aria-label to the eject (unload) button in ModelItem.svelte so screen readers announce its purpose.
- Add aria-label to the cancel download button in Selector.svelte with the specific model name being canceled.
- Improve model profile image alt text from generic 'Model' to contextual '{{modelName}} profile image'.
