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

development.md

@@ -102,9 +102,20 @@ handlers in src/ipc/. Keep new APIs in that pattern.
   looks finished the moment it starts. Hashing and copying walk tens of
   thousands of files, so every per-file update goes through progressGate
   (~10/s, phase changes forced) - never send one IPC message per file.
-- The launcher's own defaults are opt-in (the "defaults" sync category):
-  payload.defaults carries the default wine and prefix, and the receiver only
-  applies values that exist there (an unknown wine id or prefix is skipped).
+- Registry-level settings are opt-in (the "settings" sync category, shown as
+  "Sync settings"; the old name "defaults" is still accepted as an alias on
+  BOTH sides - the receiver normalizes payload.categories, so a sender from an
+  older version keeps working). payload carries defaults (default wine and
+  prefix), wineSettings (displayName + disabled per build id), prefixSettings
+  (the registry names; a settings sync never renames or creates folders -
+  that is the prefixes category), appSettings (name, wine, prefix, args, env,
+  dllOverrides, disableUmu per app id) and appOrder. The receiver only patches
+  things that already exist there: an unknown wine id / prefix / app is
+  skipped, nothing is created or deleted, and the order merge keeps local
+  entries the sender does not know at the end. Values are written through the
+  normal helpers (setWineDisplayName clears a custom label when the sender has
+  none, library.updateGame pins the prefix of prefix imports, reorderGames
+  merges by id).
 - LAN sync remembers file hashes in files/data/lansync-hashes.json, keyed by
   path with size + mtime (machine-local, never synced): equal size and mtime
   means equal bytes, so a repeat sync only stat's the tree. Hashing and the
@@ -160,6 +171,33 @@ handlers in src/ipc/. Keep new APIs in that pattern.
 - File permissions travel with a sync (manifest entry `mode`): the receiving
   side applies them after writing the bytes and repairs a file that has the
   same hash but the wrong mode without re-uploading it.
+- A sync must never walk through a symlinked ROOT. pruneTree/healUnitRoots
+  (sync), removeTree/treeSize (fsutil) and healBuild (wines) lstat their root
+  first and treat anything that is not a real directory as the link (or file)
+  it is: a build, prefix or app folder kept on another disk must not have its
+  target deleted, pruned or rewritten through the link. `listDirs()` in the
+  sync counts symlinked folders as units, so such a folder still travels - as
+  the link it is (`wineUnits` maps nested builds to their TOP folder under
+  wines/, otherwise a zip-extracted build becomes a phantom unit whose root
+  does not exist and the "Wine versions" totals grow).
+- Generated app shortcuts are file handlers too: `Exec=<launcher>
+  --launch <id> --file %f` (the field code is appended after escaping - a
+  literal % is `%%`). argv.js takes the file from `--file` or from a bare
+  trailing path (KDE appends it to Exec lines without a file field), and
+  runner.windowsPathFor passes it to the app the way Windows would: `C:\...`
+  when it sits inside the prefix's drive_c, `Z:\...` otherwise. Giving a file
+  to an app that is ALREADY running is a handoff (runGame `handoff: true`):
+  an extra untracked process, no log/playtime writes, because the app's own
+  single-instance logic is what actually opens the file.
+- A sender hashing a big unit is minutes of network silence: it pings
+  `/plwl/ping` (+token) every HEARTBEAT_MS for the whole sync, the receiver's
+  handler re-arms its popup watchdog (stage 'wait' changes nothing on screen),
+  and a receiving popup its watchdog closed reopens on the next real event -
+  only the 'done' stage ends a sync for good, and reopening NEVER asks for
+  consent again: the Accept/Decline gate is the onIncoming popup at verify
+  time (a fresh session), while the progress popup is driven by the same
+  token's events. A 'wait' event that reopens a closed popup fills the phase
+  line (`recvWaiting`) instead of leaving every line blank.
 - Tests are plain assert-by-print scripts (see test/): set PLWL_BUILD_DIR to
   a temp dir, check(), exit 1 on failure. Add one when fixing a bug.