fix: add aria-labels to SetupPage inputs and update e2e selectors

- Add aria-label attributes to all form inputs in SetupPage.tsx
  (Master Password, Confirm Password, Database Path, fail2ban Socket Path,
  Timezone, Session Duration) for accessibility and test stability
- Update e2e tests to use xpath selectors with role=alert instead of
  class-based selectors for validation messages
- Add New Context / New Page per test for browser isolation
- Fix API endpoint from /api/setup/status to /api/v1/setup
- Fix response field from setup_complete to completed
- Simplify password strength test to check aria-live text instead of
  DOM class traversal
- Remove completed task docs

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

frontend/src/pages/SetupPage.tsx

@@ -332,6 +332,7 @@ export function SetupPage(): React.JSX.Element {
                 value={values.masterPassword}
                 onChange={handleChange("masterPassword")}
                 autoComplete="new-password"
+                aria-label="Master Password"
               />
               <div className={styles.passwordStrength} aria-live="polite">
                 <div className={styles.passwordStrengthBar}>
@@ -363,6 +364,7 @@ export function SetupPage(): React.JSX.Element {
                 value={values.confirmPassword}
                 onChange={handleChange("confirmPassword")}
                 autoComplete="new-password"
+                aria-label="Confirm Password"
               />
             </Field>
 
@@ -375,6 +377,7 @@ export function SetupPage(): React.JSX.Element {
               <Input
                 value={values.databasePath}
                 onChange={handleChange("databasePath")}
+                aria-label="Database Path"
               />
             </Field>
 
@@ -387,6 +390,7 @@ export function SetupPage(): React.JSX.Element {
               <Input
                 value={values.fail2banSocket}
                 onChange={handleChange("fail2banSocket")}
+                aria-label="fail2ban Socket Path"
               />
             </Field>
 
@@ -397,6 +401,7 @@ export function SetupPage(): React.JSX.Element {
               <Input
                 value={values.timezone}
                 onChange={handleChange("timezone")}
+                aria-label="Timezone"
               />
             </Field>
 
@@ -411,6 +416,7 @@ export function SetupPage(): React.JSX.Element {
                 value={values.sessionDurationMinutes}
                 onChange={handleChange("sessionDurationMinutes")}
                 min={1}
+                aria-label="Session Duration (minutes)"
               />
             </Field>
           </div>