Add 0.10.0 milestone plan; trim ROADMAP to portable packaging

Add docs/RELEASE-0.10-PLAN.md covering the open roadmap follow-ups plus
per-job overlap policy, run-time statistics, one-line activity entries,
log-name fix, and 720p window sizing. Drop the non-portable delivery
formats (.deb, installer, AppImage, Flatpak, winget) from ROADMAP.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

docs/ROADMAP.md

@@ -45,22 +45,10 @@ Planned delivery variants:
 
 - Windows portable `.zip` with `gosentry.exe`, `README.md`, and `CHANGELOG.md`.
 - Linux portable `.tar.gz` archives for `linux-amd64` and `linux-arm64`.
-- Debian/Ubuntu `.deb` package once the Linux runtime paths are settled.
-- Windows installer later, likely Inno Setup first and MSI/WiX only if needed.
-- AppImage as a possible Linux GUI-friendly format after the core workflow is stable.
-- Flatpak only after the desktop integration story is clearer.
-- winget manifest after stable public Windows releases exist.
 
-Packaging design note:
-
-- Portable builds can keep settings and jobs next to the executable.
-- Installer/package builds should move runtime data to per-user locations:
-  `%APPDATA%\GoSentry` on Windows, and XDG directories such as
-  `~/.config/gosentry` and `~/.local/share/gosentry` on Linux.
+Portable builds keep settings and jobs next to the executable.
 
 Initial priority:
 
 1. Windows portable `.zip`.
 2. Linux portable `.tar.gz` for amd64 and arm64.
-3. Debian/Ubuntu `.deb`.
-4. Windows installer.