Make the FCC logo background transparent (#1257)

## Problem

The FCC mark is enclosed by a dark rounded-square tile. The tile
prevents the symbol from blending naturally with README, desktop, tray,
and menu-bar backgrounds.

## Changes

| Before | After |
| --- | --- |
| The three branches and terminal sit on a fixed dark tile. | The
branches and terminal sit on a transparent canvas. |
| Packaged and README artwork include the outer background. | SVG, PNG,
ICO, ICNS, and theme-aware README artwork retain only the FCC symbol. |
| The package version is 4.12.7. | The package version is 4.12.8. |

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "free-claude-code"
-version = "4.12.7"
+version = "4.12.8"
 description = "Local proxy connecting coding agents to OpenAI-compatible AI providers"
 readme = "README.md"
 requires-python = ">=3.14.0"

src/free_claude_code/assets/app-icon.icns

@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:ab8d838d3df7ec2718c353e342b771e6884d633635e5329a52b1614169d69808
-size 120734
+oid sha256:a55b7f21233557faaec825bf1017e30f11abf403f7915d71153a2c24b34336ba
+size 90091

uv.lock

@@ -620,7 +620,7 @@ wheels = [
 
 [[package]]
 name = "free-claude-code"
-version = "4.12.7"
+version = "4.12.8"
 source = { editable = "." }
 dependencies = [
     { name = "aiohttp" },