v0.2.0: ConPTY for the omp native view, usage scanner removed, menu and rendering fixes

Added: a newer ConPTY for profiles that set tsp_enabled (the omp native view). Windows' built-in ConPTY
swallows the questions omp asks at start-up, so that view never started. GhostShell now downloads Microsoft's own
Microsoft.Windows.Console.ConPTY NuGet package once (x64 only), checks the package hash and then each file's hash,
and keeps conpty.dll and OpenConsole.exe in terminal/bin/conpty/. A wrong hash, no network or a non-x64 CPU
prints one line and the tab uses the built-in ConPTY. Provenance: terminal/CONPTY_PROVENANCE.md.

Added: the omp native view through the Tern Surface Protocol. Experimental, opt-in per profile, not recommended.

Added: a log_root setting that sets where GhostShell's own logs go. With it unset nothing is logged and the code
fails loudly rather than guessing a location. The broker lifecycle log is opt-in via GHOSTSHELL_BROKER_LOG.

Changed: mouse routing follows Ghostty, and Text Edit Mode also takes the mouse. Font settings default to
Sublime's own font (the dead terminal_font setting is gone). The Ai Terminal menu is at the top level. Claude,
Auggie and Vibe profile tuning is now shipped instead of living only in the owner's User override. The Gemini profile
was removed because it does not work.

Fixed: the typing jiggle and status-update jiggle (only changed lines are redrawn, steady tab height), hover or
focus snapping a scrolled tab to the top, Nuke never clearing the terminal engine, the GhosttyError crash while
building its own message, a rewrap taking about 7 s after hiding the minimap, and leftover files from brokers that
died without cleaning up.

Removed: unit tests, notes, plans and scratch files from the shipped package.

Removed: all usage and quota features. The scanner read other CLIs' saved OAuth credentials, called the
providers' usage endpoints every 20 minutes and, for Claude Code, rewrote .credentials.json when refreshing a
token. GhostShell is not an authorised app with those providers, so it no longer does any of this. The
usage_scan_enabled and usage_refresh_minutes settings and the "Refresh Usage & Quota" command are gone.
The Launch Agent list, the menu captions and the session-info view no longer show percent remaining, reset times,
"quota exhausted" or "no usage data". An agent row shows only whether its program is installed. Use omp usage
for real quota figures. A test (tests/test_no_usage_in_code.py) fails if usage code is ever added back.

Changed: an agent whose program is not installed is no longer listed on the Launch Agent list, and its menu
entries are hidden. Previously it was listed and marked "Not installed". The Cody profile was removed.

Changed: agents are launched from the Ai Terminal > Agents and Ai Terminal > Shells submenus, sorted A-Z,
instead of a picker. Agents that are not installed are hidden. The "Launch Agent…" picker, its palette entry and its
Ctrl+Alt+N shortcut are gone, and so are the picker code, the folder picker that went with it, the "Default Profile" item and the sidebar's
"Open Ai Terminal here…". The same two submenus are in the sidebar's right-click menu. The submenus are
built ahead of time by tools/regen_agent_menu.py (Sublime has no API for adding menu items while it runs), and a test
fails if the menu and the agent list ever differ.