fix(macos): pad dock icon to Apple icon grid (#1169)

* fix(macos): pad dock icon to Apple icon grid

The macOS .icns artwork filled the canvas edge-to-edge, so the dock icon
rendered larger than native apps. Replace icon.icns with a build whose artwork
is scaled to an ~824px body centred on a 1024px transparent canvas (Apple's
icon grid). macOS-only asset; Windows .ico and Linux PNGs unchanged. Refs #1166.

* fix(macos): skip the icns app-icon in dev to avoid a launch crash

Tauri's dev-only macOS path sets the app icon from icon.icns via
NSImage::initWithData(...).expect(...) (RunEvent::Ready); the padded icns
makes that return nil and abort at launch — release builds are unaffected.
Add a dev config override (tauri.dev.conf.json) that drops icon.icns from
bundle.icon so the dev app icon falls back to a PNG; tauri:dev passes it via
--config. Production bundling keeps the padded icon.icns. Refs #1166.

* docs(changelog): add entry for macOS dock icon padding (PR #1169)

CHANGELOG.md

@@ -239,6 +239,12 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 * Guest suggestions no longer get silently lost or stuck on "waiting on host": overlapping host updates are serialised, a lost suggestion is re-sent (with a notice if it still can't get through), and a flaky join no longer leaves a duplicate suggestion list on the server.
 * Pasted invites are rejected unless they point at a normal http/https server address.
 
+### macOS dock icon larger than native apps
+
+**By [@Psychotoxical](https://github.com/Psychotoxical), PR [#1169](https://github.com/Psychotoxical/psysonic/pull/1169)**, closes [#1166](https://github.com/Psychotoxical/psysonic/issues/1166)
+
+* On macOS the dock icon was rendered edge-to-edge and looked larger than other apps; it is now padded to Apple's icon grid so it matches native sizing.
+
 ## Under the Hood
 
 ### ESLint setup and a strict lint pass over the frontend