refactor: extract magic values into named constant modules

Scattered numeric literals had no names at their use sites, making it
impossible to know whether two identical values were intentionally the
same or coincidentally equal. Moving them to typed constants makes the
relationship explicit and ensures a single edit propagates everywhere.

src/main/constants/input.ts

@@ -0,0 +1,3 @@
+export const TRIGGER_THRESHOLD = 8
+export const DEDUP_WINDOW_MS = 40
+export const HOTPLUG_SCAN_INTERVAL_MS = 3_000

src/main/input/gamepadReader.ts

@@ -32,6 +32,7 @@
 import * as fs from 'node:fs'
 import * as path from 'node:path'
 import type { BrowserWindow } from 'electron'
+import { DEDUP_WINDOW_MS, HOTPLUG_SCAN_INTERVAL_MS, TRIGGER_THRESHOLD } from '../constants/input'
 
 // evdev input_event auf 64-bit Linux:
 // { u64 tv_sec (8 Bytes), u64 tv_usec (8 Bytes), u16 type (2), u16 code (2), s32 value (4) } = 24 Bytes
@@ -70,16 +71,10 @@ const BUTTON_MAP: Record<number, string> = {
 }
 
 const STICK_THRESHOLD = 16384  // ~50% von 32767
-// Trigger-Schwellwert: Achsenwert > 0 (nicht gedrückt) bis ~255–1023 je Controller
-const TRIGGER_THRESHOLD = 8
 const REPEAT_INITIAL_MS = 400
 const REPEAT_INTERVAL_MS = 150
 // Trigger-Achsen sollen kein Auto-Repeat auslösen (300s-Sprünge nicht wiederholen)
 const NO_REPEAT_ABS_CODES = new Set([ABS_Z, ABS_RZ])
-const SCAN_INTERVAL_MS = 3000
-// Bluetooth-/Steam-Setups können dieselbe Eingabe über mehrere Devices liefern.
-// Nahezu zeitgleiche identische Events werden global entdoppelt.
-const DUPLICATE_EVENT_WINDOW_MS = 40
 
 interface AxisState {
   key: string | null
@@ -367,7 +362,7 @@ export function startGamepadReader(getWindow: () => BrowserWindow | null): () =>
   const onKey = (key: string): void => {
     const now = Date.now()
     const lastAt = lastKeyAt.get(key) ?? 0
-    if (now - lastAt < DUPLICATE_EVENT_WINDOW_MS) return
+    if (now - lastAt < DEDUP_WINDOW_MS) return
     lastKeyAt.set(key, now)
 
     const win = getWindow()
@@ -427,7 +422,7 @@ export function startGamepadReader(getWindow: () => BrowserWindow | null): () =>
   }
 
   scanDevices()
-  const timer = setInterval(scanDevices, SCAN_INTERVAL_MS)
+  const timer = setInterval(scanDevices, HOTPLUG_SCAN_INTERVAL_MS)
 
   return () => {
     clearInterval(timer)

src/renderer/src/components/PlaybackOverlay.tsx

@@ -2,6 +2,7 @@ import { useCallback, useEffect, useRef, useState } from 'react'
 import { GamepadHintItem } from './GamepadPrompt'
 import { ClapperboardIcon, EyeIcon, GamepadIcon, PauseIcon, PlayIcon, QualityIcon, StopIcon } from './Icons'
 import { formatCount, formatTimestamp } from '../lib/formatting'
+import { DOUBLE_TAP_MS, OVERLAY_HIDE_DELAY_MS } from '../constants/playback'
 
 interface PlaybackOverlayProps {
   playState: 'playing' | 'paused'
@@ -30,9 +31,6 @@ interface PlaybackOverlayProps {
 }
 
 
-const HIDE_DELAY_MS = 5_000
-const DOUBLE_TAP_MS = 300
-
 export function PlaybackOverlay({
   playState,
   durationSeconds,
@@ -81,7 +79,7 @@ export function PlaybackOverlay({
 
   const scheduleHide = useCallback(() => {
     clearHideTimer()
-    hideTimerRef.current = setTimeout(() => setVisible(false), HIDE_DELAY_MS)
+    hideTimerRef.current = setTimeout(() => setVisible(false), OVERLAY_HIDE_DELAY_MS)
   }, [clearHideTimer])
 
   /** Call on any user interaction to show overlay and reset auto-hide timer. */

src/renderer/src/components/VideoPlayer.tsx

@@ -1,5 +1,6 @@
 import Hls from 'hls.js'
 import { forwardRef, useEffect, useImperativeHandle, useRef } from 'react'
+import { POSITION_REPORT_INTERVAL_MS } from '../constants/playback'
 
 export interface VideoPlayerHandle {
   seek(delta: number): void
@@ -24,8 +25,6 @@ interface Props {
   onTimeUpdate?: (seconds: number) => void
 }
 
-const POSITION_REPORT_INTERVAL_MS = 5_000
-
 export const VideoPlayer = forwardRef<VideoPlayerHandle, Props>(
   ({ hlsUrl, startPosition, isLive, vodId, durationSeconds, onPlaying, onPaused, onEnded, onError, onTimeUpdate }, ref) => {
     const videoRef = useRef<HTMLVideoElement>(null)

src/renderer/src/constants/input.ts

@@ -0,0 +1,3 @@
+export const AXIS_THRESHOLD = 0.5
+export const REPEAT_INITIAL_MS = 400
+export const REPEAT_INTERVAL_MS = 150

src/renderer/src/constants/playback.ts

@@ -0,0 +1,3 @@
+export const OVERLAY_HIDE_DELAY_MS = 5_000
+export const DOUBLE_TAP_MS = 300
+export const POSITION_REPORT_INTERVAL_MS = 5_000

src/renderer/src/constants/ui.ts

@@ -0,0 +1,4 @@
+export const CARD_W = 260
+export const CARD_GAP = 16
+export const STREAM_W = 220
+export const STREAM_GAP = 14

src/renderer/src/input/gamepad.ts

@@ -20,6 +20,8 @@
  *   Axis  0 (left stick X) → Left/Right
  */
 
+import { AXIS_THRESHOLD, REPEAT_INITIAL_MS, REPEAT_INTERVAL_MS } from '../constants/input'
+
 const BUTTON_MAP: Record<number, string> = {
   0: 'Enter',   // A
   1: 'Escape',  // B
@@ -35,10 +37,6 @@ const BUTTON_MAP: Record<number, string> = {
   15: 'ArrowRight'
 }
 
-const AXIS_THRESHOLD = 0.5
-const REPEAT_INITIAL_MS = 400
-const REPEAT_INTERVAL_MS = 150
-
 interface AxisRepeat {
   key: string | null
   heldSince: number

src/renderer/src/screens/BrowseScreen.tsx

@@ -3,6 +3,7 @@ import { GamepadHintItem } from '../components/GamepadPrompt'
 import LanguageBadge from '../components/LanguageBadge'
 import type { FollowedChannelInfo, GameInfo } from '../types/t4sd'
 import { formatViewers, formatViewersFull } from '../lib/formatting'
+import { STREAM_GAP, STREAM_W } from '../constants/ui'
 
 interface Props {
   hasFocus: boolean
@@ -15,8 +16,6 @@ interface Props {
 type LoadState = 'loading' | 'ok' | 'error'
 type FocusRegion = 'shelf' | 'grid'
 
-const STREAM_W = 220
-const STREAM_GAP = 14
 
 export default function BrowseScreen({
   hasFocus,

src/renderer/src/screens/ChannelScreen.tsx

@@ -13,6 +13,7 @@ import {
   formatViewers,
   formatWatchedAt
 } from '../lib/formatting'
+import { CARD_GAP, CARD_W } from '../constants/ui'
 
 interface Props {
   channel: FollowedChannelInfo
@@ -21,9 +22,6 @@ interface Props {
 
 type FocusRegion = 'hero' | 'shelf' | 'chapters'
 
-const CARD_W = 260
-const CARD_GAP = 16
-
 function resolveThumbnail(url: string | undefined, w = 1280, h = 720): string | undefined {
   return url?.replace('{width}', String(w)).replace('{height}', String(h))
 }