Upgrade ESLint to v9 with flat config (#9680)

* Upgrade ESLint to v9 with flat config

- Upgrade eslint from v8 to v9.18.0
- Migrate from .eslintrc.js to eslint.config.mjs (flat config)
- Upgrade typescript-eslint to v8.20.0 (unified package)
- Replace eslint-plugin-import with eslint-plugin-import-x for flat config support
- Add globals package for environment globals
- Update eslint-plugin-bsky-internal with proper meta objects for ESLint v9
- Fix deprecated context.getScope() API usage
- Update bskyembed to use flat config
- Remove deprecated --ext flag from lint scripts
- Configure rules to maintain previous behavior while using new ESLint version

* Fix varsIgnorePattern to require character after underscore

Restore the original pattern `^_.+` instead of `^_` so that lingui's
`const { _ } = useLingui()` will still be flagged when unused.

* Update ESLint rule tests for flat config format

- Update RuleTester to use flat config languageOptions instead of
  eslintrc parser format
- Remove duplicate test case that ESLint v9 now detects
- Add Jest globals for test files

* update eslint package versions

* lint android a11y

* enable typechecked rules, switch them to warn

* fix yarn lock ci

* Fix CI failure

* Remove unused globals?

* Organize a bit, add quiet to main lint command

* Allow ternary

---------

Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: Eric Bailey <git@esb.lol>

src/view/com/composer/text-input/TextInput.tsx

@@ -14,7 +14,9 @@ import {
 import {AppBskyRichtextFacet, RichText} from '@atproto/api'
 import PasteInput, {
   type PastedFile,
-  type PasteInputRef, // @ts-expect-error no types when installing from github
+  type PasteInputRef,
+  // @ts-expect-error no types when installing from github
+  // eslint-disable-next-line import-x/no-unresolved
 } from '@mattermost/react-native-paste-input'
 
 import {POST_IMG_MAX} from '#/lib/constants'

src/view/com/posts/PostFeed.tsx

@@ -437,7 +437,6 @@ let PostFeed = ({
           for (const page of data.pages) {
             for (const slice of page.slices) {
               const item = slice.items.find(
-                // eslint-disable-next-line @typescript-eslint/no-shadow
                 item => item.uri === slice.feedPostUri,
               )
               if (

src/view/com/testing/TestCtrls.e2e.tsx

@@ -1,9 +1,9 @@
 import {useState} from 'react'
-import {LogBox, Pressable, View, TextInput} from 'react-native'
+import {LogBox, Pressable, TextInput, View} from 'react-native'
 import {useQueryClient} from '@tanstack/react-query'
 
 import {BLUESKY_PROXY_HEADER} from '#/lib/constants'
-import {useSessionApi, useAgent} from '#/state/session'
+import {useAgent, useSessionApi} from '#/state/session'
 import {useLoggedOutViewControls} from '#/state/shell/logged-out'
 import {useOnboardingDispatch} from '#/state/shell/onboarding'
 import {navigate} from '../../../Navigation'
@@ -50,6 +50,8 @@ export function TestCtrls() {
   return (
     <View style={{position: 'absolute', top: 100, right: 0, zIndex: 100}}>
       <TextInput
+        accessibilityLabel="Text input field"
+        accessibilityHint="Enter proxy header"
         testID="e2eProxyHeaderInput"
         onChangeText={val => setProxyHeader(val as any)}
         onSubmitEditing={() => {

src/view/com/util/Alert.web.tsx

@@ -3,12 +3,10 @@ import {type AlertButton, type AlertStatic} from 'react-native'
 class WebAlert implements Pick<AlertStatic, 'alert'> {
   public alert(title: string, message?: string, buttons?: AlertButton[]): void {
     if (buttons === undefined || buttons.length === 0) {
-      // eslint-disable-next-line no-alert
       window.alert([title, message].filter(Boolean).join('\n'))
       return
     }
 
-    // eslint-disable-next-line no-alert
     const result = window.confirm([title, message].filter(Boolean).join('\n'))
 
     if (result === true) {

src/view/com/util/forms/Button.tsx

@@ -153,9 +153,9 @@ export function Button({
     async (event: GestureResponderEvent) => {
       event.stopPropagation()
       event.preventDefault()
-      withLoading && setIsLoading(true)
+      if (withLoading) setIsLoading(true)
       await onPress?.(event)
-      withLoading && setIsLoading(false)
+      if (withLoading) setIsLoading(false)
     },
     [onPress, withLoading],
   )

src/view/com/util/text/Text.tsx

@@ -51,6 +51,7 @@ function Text_DEPRECATED({
   if (__DEV__) {
     if (!emoji && childHasEmoji(children)) {
       logger.warn(
+        // eslint-disable-next-line @typescript-eslint/restrict-template-expressions, @typescript-eslint/no-base-to-string
         `Text: emoji detected but emoji not enabled: "${children}"\n\nPlease add <Text emoji />'`,
       )
     }