fix(walkthrough): stop the importance tag reading as a review finding

The "Critical" pill was painted in the status-error colour, so a stop marked
because it drives the change read as a severity reported against the code —
the one thing this feature never does. It is now "Key change", carries its
emphasis with weight and an outline rather than a status colour, and both tags
state their meaning in a tooltip. The panel links the guide from its header,
and the guide gained a section on what the tags mean and what they do not.

Also corrects two German strings that translated the noun "stop" as the verb.

packages/ui/src/components/views/walkthrough/WalkthroughStream.tsx

@@ -2,6 +2,7 @@ import { memo, useCallback, useEffect, useMemo, useRef, useState } from 'react';
 import { Icon } from '@/components/icon/Icon';
 import { FileTypeIcon } from '@/components/icons/FileTypeIcon';
 import { Button } from '@/components/ui/button';
+import { Tooltip, TooltipContent, TooltipTrigger } from '@/components/ui/tooltip';
 import { useI18n } from '@/lib/i18n';
 import { groupHunksByFile } from '@/lib/walkthrough/model';
 import type { WalkthroughStopView, WalkthroughView } from '@/lib/walkthrough/model';
@@ -20,8 +21,13 @@ interface WalkthroughStreamProps {
   wrapLines: boolean;
 }
 
+// Importance says where to spend attention, not what is wrong: a stop is marked
+// because it drives the rest of the change, never because something was found in
+// it. A red pill said the opposite — status colours are read as findings, and a
+// walkthrough deliberately hands out no verdicts — so the emphasis is carried by
+// weight and an outline instead, and the tooltip states the axis outright.
 const IMPORTANCE_CLASS: Record<WalkthroughStopImportance, string> = {
-  critical: 'bg-status-error/10 text-status-error',
+  critical: 'border border-[var(--interactive-border)] font-medium text-foreground',
   normal: 'bg-surface-muted text-muted-foreground',
   context: 'bg-surface-muted text-muted-foreground',
 };
@@ -41,11 +47,22 @@ const StopHeader = ({ stopView }: { stopView: WalkthroughStopView }) => {
             exactly as tall as one without: vertical padding on a smaller type
             size was pushing past the tallest element in the row. */}
         {stop.importance !== 'normal' && (
-          <span className={cn('typography-micro flex h-5 items-center rounded px-1.5 leading-none', IMPORTANCE_CLASS[stop.importance])}>
-            {stop.importance === 'critical'
-              ? t('walkthrough.importance.critical')
-              : t('walkthrough.importance.context')}
-          </span>
+          <Tooltip>
+            <TooltipTrigger
+              className={cn('typography-micro flex h-5 items-center rounded px-1.5 leading-none', IMPORTANCE_CLASS[stop.importance])}
+            >
+              {stop.importance === 'critical'
+                ? t('walkthrough.importance.critical')
+                : t('walkthrough.importance.context')}
+            </TooltipTrigger>
+            <TooltipContent className="max-w-64">
+              <p className="typography-micro leading-tight">
+                {stop.importance === 'critical'
+                  ? t('walkthrough.importance.criticalHint')
+                  : t('walkthrough.importance.contextHint')}
+              </p>
+            </TooltipContent>
+          </Tooltip>
         )}
       </div>
       <p className="typography-body text-muted-foreground">{stop.prose}</p>

packages/ui/src/components/views/walkthrough/WalkthroughView.tsx

@@ -10,7 +10,9 @@ import {
   DropdownMenuSeparator,
   DropdownMenuTrigger,
 } from '@/components/ui/dropdown-menu';
+import { Tooltip, TooltipContent, TooltipTrigger } from '@/components/ui/tooltip';
 import { useI18n, type Locale } from '@/lib/i18n';
+import { openExternalUrl } from '@/lib/url';
 import { buildWalkthroughView } from '@/lib/walkthrough/model';
 import type { WalkthroughSource, WalkthroughWorkingTreeScope } from '@/lib/walkthrough/types';
 import { ModelSelector } from '@/components/sections/agents/ModelSelector';
@@ -41,6 +43,12 @@ interface WalkthroughViewProps {
 
 const SCOPES: WalkthroughWorkingTreeScope[] = ['all', 'staged', 'working'];
 
+// What a walkthrough is — and what it deliberately is not — cannot be read off
+// the panel: the first question users asked about it was whether its marks were
+// review findings. The guide answers that, so it is reachable from the surface
+// itself rather than only from the release announcement.
+const WALKTHROUGH_GUIDE_URL = 'https://docs.openchamber.dev/walkthrough/';
+
 // DropdownMenuLabel defaults to the same size and weight as its items, which
 // makes a heading read as another choice. This matches SelectLabel, the
 // treatment used by the worktree picker.
@@ -524,6 +532,25 @@ export const WalkthroughView = ({ directory }: WalkthroughViewProps) => {
         </DropdownMenu>
 
         <div className="ml-auto flex min-w-0 items-center gap-1">
+          <Tooltip>
+            <TooltipTrigger asChild>
+              <Button
+                type="button"
+                variant="ghost"
+                size="sm"
+                aria-label={t('walkthrough.help.guide')}
+                onClick={() => {
+                  void openExternalUrl(WALKTHROUGH_GUIDE_URL);
+                }}
+              >
+                <Icon name="question" className="size-4" />
+              </Button>
+            </TooltipTrigger>
+            <TooltipContent>
+              <p className="typography-micro leading-tight">{t('walkthrough.help.guide')}</p>
+            </TooltipContent>
+          </Tooltip>
+
           {/* A walkthrough nobody can read is worth nothing, so the prose
               language is a per-review choice like the model — defaulting to the
               interface language, which is the best evidence of what the reader