ui: UI/chat form follow ups (#26743)

* ui: split the markdown rendering setting per surface

User content and thinking get their own toggle again, so turning off
markdown for a message leaves reasoning blocks formatted. Both default
to markdown. A stored renderContentAsRawText unfolds onto the user key
and is dropped from the config.

File mentions render as badges in the raw text path too, through a
narrow pass over [name](file://path) that leaves everything else
untouched.

* ui: let the rich chat input scroll past its max height

The contenteditable renderer caps its height with max-height but had no
overflow rule, so a long buffer overflowed into the input area wrapper
and got clipped by its overflow-hidden, leaving no way to reach the
bottom of the message. The textarea renderer scrolls natively and was
never affected.

* ui: apply the new lint and format config

* ui: move the render keys unfolding into the migration service

Address review from @allozaur: the settings store no longer rewrites
persisted config on load, the raw text toggle now unfolds onto the
per-surface render keys in migration.service.ts, next to the other
config migrations. The mention scanner flag and the directory path
suffix become named constants.

tools/ui/src/lib/constants/mention-badge.ts

@@ -10,6 +10,9 @@ export const MENTION_BADGE_CLASSNAME =
 
 export const MENTION_BADGE_ICON_CLASSNAME = 'h-3 w-3 shrink-0';
 
+/** Regex flag that makes the mention scanner walk every link in a message instead of the first. */
+export const MENTION_LINK_SCAN_FLAGS = 'g';
+
 /**
  * SVG attributes shared by the DOM-built and hast-built badge icons.
  * The tokenizer applies them via `setAttribute`, the rehype plugin

tools/ui/src/lib/constants/path-display.ts

@@ -12,6 +12,9 @@ import { UrlProtocol } from '$lib/enums';
 export const CWD_CHANGED_PREFIX = 'Set working directory to ';
 export const CWD_CLEARED_TEXT = 'Working directory cleared';
 
+/** Trailing separator that marks a path as a directory. */
+export const DIRECTORY_PATH_SUFFIX = '/';
+
 export const HOME_TILDE = '~';
 export const HOME_TILDE_PREFIX = '~/'; // tilde plus path separator
 

tools/ui/src/lib/constants/settings-keys.ts

@@ -41,7 +41,8 @@ export const SETTINGS_KEYS = {
 	// Performance
 	PRE_ENCODE_CONVERSATION: 'preEncodeConversation',
 	PRESENCE_PENALTY: 'presence_penalty',
-	RENDER_CONTENT_AS_RAW_TEXT: 'renderContentAsRawText',
+	RENDER_THINKING_AS_MARKDOWN: 'renderThinkingAsMarkdown',
+	RENDER_USER_CONTENT_AS_MARKDOWN: 'renderUserContentAsMarkdown',
 	// Penalties
 	REPEAT_LAST_N: 'repeat_last_n',
 	REPEAT_PENALTY: 'repeat_penalty',

tools/ui/src/lib/constants/settings-registry.ts

@@ -230,10 +230,18 @@ const SETTINGS_REGISTRY: Record<string, SettingsSectionEntry> = {
 				type: SettingsFieldType.CHECKBOX
 			},
 			{
-				defaultValue: false,
-				help: 'Display user, system and thinking content as plain text instead of formatted Markdown. Markdown is the default so that @-mention badges render in sent messages.',
-				key: SETTINGS_KEYS.RENDER_CONTENT_AS_RAW_TEXT,
-				label: 'Render content as raw text',
+				defaultValue: true,
+				help: 'Render user messages using markdown formatting in the chat. Turn this off to keep a message exactly as typed; @-mention badges show either way.',
+				key: SETTINGS_KEYS.RENDER_USER_CONTENT_AS_MARKDOWN,
+				label: 'Render user content as Markdown',
+				section: SETTINGS_SECTION_SLUGS.DISPLAY,
+				type: SettingsFieldType.CHECKBOX
+			},
+			{
+				defaultValue: true,
+				help: 'Render the reasoning/thinking block content as formatted Markdown instead of plain text.',
+				key: SETTINGS_KEYS.RENDER_THINKING_AS_MARKDOWN,
+				label: 'Render thinking as Markdown',
 				section: SETTINGS_SECTION_SLUGS.DISPLAY,
 				type: SettingsFieldType.CHECKBOX
 			},