Ship the portable X11 bundle lifecycle

Implement milestone 2 around a portable X11 release bundle instead of\nkeeping distro packages as the only end-user path.\n\nAdd make/package scripts plus a portable installer helper that builds the\ntarball, creates a user-scoped venv install, manages the user service, handles\nupgrade rollback, and supports uninstall with optional purge.\n\nFlip the end-user docs to the portable bundle, add a dedicated install guide\nand validation matrix, and leave the roadmap milestone open only for the\nremaining manual distro validation evidence.\n\nValidation: python3 -m py_compile src/*.py packaging/portable/portable_installer.py tests/test_portable_bundle.py; PYTHONPATH=src python3 -m unittest tests.test_portable_bundle; PYTHONPATH=src python3 -m unittest tests.test_aman_cli tests.test_diagnostics tests.test_portable_bundle; PYTHONPATH=src python3 -m unittest discover -s tests -p 'test_*.py'

docs/persona-and-distribution.md

@@ -36,18 +36,17 @@ Design implications:
 
 The current release channels are:
 
-1. Current end-user channel: Debian package (`.deb`) for Ubuntu/Debian users.
-2. Secondary: Arch package inputs (`PKGBUILD` + source tarball).
-3. Developer: wheel and sdist from `python -m build`.
-
-The portable X11 installer is the GA target channel, not the current shipped
-channel.
+1. Current canonical end-user channel: portable X11 bundle (`aman-x11-linux-<version>.tar.gz`).
+2. Secondary packaged channel: Debian package (`.deb`) for Ubuntu/Debian users.
+3. Secondary maintainer channel: Arch package inputs (`PKGBUILD` + source tarball).
+4. Developer: wheel and sdist from `python -m build`.
 
 ## GA Target Support Contract
 
 For X11 GA, Aman supports:
 
 - X11 desktop sessions only.
+- System CPython `3.10`, `3.11`, or `3.12` for the portable installer.
 - Runtime dependencies installed from the distro package manager.
 - `systemd --user` as the supported daily-use path.
 - `aman run` as the foreground setup, support, and debugging path.
@@ -59,6 +58,14 @@ For X11 GA, Aman supports:
 not mean native-package parity or exhaustive certification for every Linux
 variant.
 
+## Canonical end-user lifecycle
+
+- Install: extract the portable bundle and run `./install.sh`.
+- Update: extract the newer portable bundle and run its `./install.sh`.
+- Uninstall: run `~/.local/share/aman/current/uninstall.sh`.
+- Purge uninstall: run `~/.local/share/aman/current/uninstall.sh --purge`.
+- Recovery: `aman doctor` -> `aman self-check` -> `journalctl --user -u aman` -> `aman run --verbose`.
+
 ## Out of Scope for X11 GA
 
 - Wayland production support.