feat: enhance diagnostic settings UI with reset button and unlimited option

- Add reset button to restore default value (50 diagnostics)
- Add unlimited checkbox that sets value to -1 and displays ∞ symbol
- Update checkbox label to 'Automatically include diagnostics in context'
- Clarify description to explain automatic vs manual inclusion behavior
- Update all 18 language translation files with new UI strings

Author: hannesrudolph

webview-ui/src/components/settings/ContextManagementSettings.tsx

@@ -229,8 +229,30 @@ export const ContextManagementSettings = ({
 							value={[maxDiagnosticMessages ?? 50]}
 							onValueChange={([value]) => setCachedStateField("maxDiagnosticMessages", value)}
 							data-testid="max-diagnostic-messages-slider"
+							disabled={maxDiagnosticMessages === -1}
 						/>
-						<span className="w-10">{maxDiagnosticMessages ?? 50}</span>
+						<span className="w-10">
+							{maxDiagnosticMessages === -1 ? "∞" : (maxDiagnosticMessages ?? 50)}
+						</span>
+						<Button
+							variant="ghost"
+							size="sm"
+							onClick={() => setCachedStateField("maxDiagnosticMessages", 50)}
+							title={t("settings:contextManagement.diagnostics.maxMessages.resetTooltip")}
+							className="p-1 h-6 w-6"
+							disabled={maxDiagnosticMessages === 50}>
+							<span className="codicon codicon-discard" />
+						</Button>
+					</div>
+					<div className="flex items-center gap-2 mt-2">
+						<VSCodeCheckbox
+							checked={maxDiagnosticMessages === -1}
+							onChange={(e: any) =>
+								setCachedStateField("maxDiagnosticMessages", e.target.checked ? -1 : 50)
+							}
+							data-testid="max-diagnostic-messages-unlimited-checkbox">
+							{t("settings:contextManagement.diagnostics.maxMessages.unlimited")}
+						</VSCodeCheckbox>
 					</div>
 					<div className="text-vscode-descriptionForeground text-sm mt-1">
 						{t("settings:contextManagement.diagnostics.maxMessages.description")}

webview-ui/src/i18n/locales/ca/settings.json

@@ -490,12 +490,14 @@
 		},
 		"diagnostics": {
 			"includeMessages": {
-				"label": "Include diagnostic messages in context",
-				"description": "When enabled, diagnostic messages (errors, warnings) will be included when using @problems or when files with diagnostics are read."
+				"label": "Automatically include diagnostics in context",
+				"description": "When enabled, diagnostic messages (errors) from edited files will be automatically included in the context. You can always manually include all workspace diagnostics using @problems."
 			},
 			"maxMessages": {
 				"label": "Maximum diagnostic messages",
-				"description": "Maximum number of diagnostic messages to include per file when using @problems or when automatic inclusion is enabled. Higher values provide more context but increase token usage."
+				"description": "Maximum number of diagnostic messages to include per file. This limit applies to both automatic inclusion (when checkbox is enabled) and manual @problems mentions. Higher values provide more context but increase token usage.",
+				"resetTooltip": "Reset to default value (50)",
+				"unlimited": "Unlimited diagnostic messages"
 			}
 		},
 		"condensingThreshold": {