allozaur/feat/chat slash commands (#26716)

* base : slash-command/misc foundation - model icon and focus-selector constants

* feat : slash-command picker and command parsing helpers

* refactor : wire command and @-mention pickers into the chat form

* ui : improve model selector keyboard navigation and load/dismiss

* feat: Unify markdown/raw-text rendering under one setting with migration

* fix: Misc fixes - tool-call subtitle, assistant wrap, progress guards

* feat: Clamp and style numeric settings inputs from registry bounds

tools/ui/src/lib/utils/command-token.ts

@@ -0,0 +1,31 @@
+/**
+ * Slash-command token detection for the chat form. Valid only at offset 0.
+ */
+export function findCommandToken(
+	value: string
+): { name: string; args: string; end: number } | null {
+	if (!value.startsWith('/')) return null;
+
+	const rest = value.slice(1);
+	const spaceIdx = rest.search(/\s/);
+	const name = spaceIdx === -1 ? rest : rest.slice(0, spaceIdx);
+	const args = spaceIdx === -1 ? '' : rest.slice(spaceIdx + 1);
+
+	return { name, args, end: value.length };
+}
+
+/**
+ * Stable signature of a slash-command token for use as a "dismissed"
+ * marker: while the picker is closed and this exact token is still intact,
+ * the picker does not re-open on in-token edits.
+ */
+export interface CommandDismissSnapshot {
+	name: string;
+	args: string;
+}
+
+export function takeCommandDismissSnapshot(value: string): CommandDismissSnapshot | null {
+	const token = findCommandToken(value);
+	if (!token) return null;
+	return { name: token.name, args: token.args };
+}

tools/ui/src/lib/utils/index.ts

@@ -198,6 +198,13 @@ export {
 	type MentionDismissSnapshot
 } from './mention-token';
 
+// Slash-command token detection (for the `/`-triggered command picker)
+export {
+	findCommandToken,
+	takeCommandDismissSnapshot,
+	type CommandDismissSnapshot
+} from './command-token';
+
 // Mention-chip visual contract shared by the rehype file-badge plugin,
 // plus the `[name](file://...)` link helpers the mention picker splices in
 export {

tools/ui/src/lib/utils/progress.ts

@@ -19,7 +19,9 @@ export function modelLoadStageLabel(stage: ApiModelLoadStage): string {
 export function modelLoadFraction(progress: ModelLoadProgress | null): number {
 	if (!progress) return 0;
 
-	const { stages, current, value } = progress;
+	// The server may emit a progress event before the stage plan is known, so
+	// `stages` can be absent. Fall back to the raw value in that case.
+	const { stages = [], current, value } = progress;
 	const tailCount = Math.max(stages.length - 1, 0);
 	const textCeiling = 1 - tailCount * MODEL_LOAD_TAIL_SHARE;
 	const idx = stages.indexOf(current);
@@ -39,5 +41,7 @@ export function modelLoadProgressText(progress: ModelLoadProgress | null): strin
 	if (!progress) return null;
 
 	const label = modelLoadStageLabel(progress.current);
+	if (!label) return null;
+
 	return `${label} ${Math.round(modelLoadFraction(progress) * 100)}%`;
 }