improvemets & fixes:

- added 'open with' handling to desktop shortcuts
- move logs button to app configuration
- fix sync progress disappearing after long hashing
- fix sync double file counter
- merge wine and proton prefix folders via symlink

src/runner.js

@@ -221,6 +221,25 @@ function parseArgs(args) {
   return out
 }
 
+// A file handed over from the Linux file manager ("Open with" on an app
+// shortcut) has to reach the Windows app as a WINDOWS path, the way it would
+// on Windows: C:\ for anything inside the prefix's C: drive, and wine's Z:\
+// mapping (the filesystem root) for everything else.
+function windowsPathFor(file, prefixDir) {
+  let abs = String(file || '')
+  try {
+    abs = fs.realpathSync(abs)
+  } catch {}
+  try {
+    const driveC = fs.realpathSync(path.join(prefixDir, 'drive_c'))
+    const rel = path.relative(driveC, abs)
+    if (rel && !rel.startsWith('..') && !path.isAbsolute(rel)) {
+      return 'C:\\' + rel.split(path.sep).join('\\')
+    }
+  } catch {}
+  return `Z:${abs.split(path.sep).join('\\')}`
+}
+
 const GRACE_MS = 60000
 
 // Live playtime: while the game runs, update ONLY the tiny playtime file
@@ -250,13 +269,15 @@ function openLatestLog(gameId) {
   return fs.createWriteStream(logFile, { flags: 'w' })
 }
 
-async function runGame({ game, wine, systemWine, onExit }) {
+async function runGame({ game, wine, systemWine, onExit, openFile, handoff = false }) {
   await healPrefixOnce(game)
   const isProton = wine && wine.type === 'proton'
-  const { env } = buildEnv({ game, wine })
+  const { env, prefixDir } = buildEnv({ game, wine })
   const exe = game.exePath
   const workdir = game.workdir || path.dirname(exe)
   const argList = parseArgs(game.args)
+  // an opened file is an argument to the exe, exactly like Windows' "Open with"
+  if (openFile) argList.push(windowsPathFor(openFile, prefixDir))
 
   let cmd
   let base
@@ -275,7 +296,10 @@ async function runGame({ game, wine, systemWine, onExit }) {
       child = spawn(cmd, base, {
         cwd: workdir,
         env,
-        stdio: ['ignore', 'pipe', 'pipe'],
+        // a handoff (a file given to an already running app) is not tracked:
+        // its pipes are left unread, so the output goes nowhere instead of
+        // filling up and blocking the app
+        stdio: handoff ? 'ignore' : ['ignore', 'pipe', 'pipe'],
         detached: true
       })
     } catch (err) {
@@ -293,6 +317,12 @@ async function runGame({ game, wine, systemWine, onExit }) {
     })
     child.once('spawn', () => {
       started = true
+      // a handoff never writes the app's log or playtime: the tracked run owns
+      // both, and truncating the live log would destroy what it is writing
+      if (handoff) {
+        child.unref()
+        return resolve({ pid: child.pid, logFile: null })
+      }
       const logFile = latestLogPath(game.id)
       const ws = openLatestLog(game.id)
       // a launch line of our own before the raw wine output: when a game
@@ -365,4 +395,4 @@ function runAdHoc({ openPath, wine, systemWine, prefix, onExit }) {
   return runGame({ game, wine, systemWine, onExit })
 }
 
-module.exports = { buildEnv, runGame, runTool, runAdHoc, parseArgs, latestLogPath }
+module.exports = { buildEnv, runGame, runTool, runAdHoc, parseArgs, latestLogPath, windowsPathFor }