Antigravity health probe filled my C: drive (56 GB of _MEI orphans); pre-#12008 leftovers are never cleaned

What happened

My C: drive filled completely (268 GB used, ~5 MB free). The filler: 51 Temp\_MEI* PyInstaller temp dirs totaling ~56 GB created within a day by T3 (plus 44 more the day before, also nuked).

Root cause (verified live)

On my Nightly build (predates #12008), the Antigravity provider status probe boots the real 430 MB agy_acp_server.exe PyInstaller bundle roughly every minute (providerHealthRefreshInterval default 1 min) plus once at boot, just to read status. Each launch extracts ~1 GB to %LOCALAPPDATA%\Temp\_MEI*, and the teardown kills it before the bootloader cleans up, orphaning the directory.

Evidence:

• Process trap caught the full chain live: T3 server (bin.mjs) -> agy_acp_server.exe (no args) -> localharness grandchild, minutes after I re-enabled the provider.
• T3-managed binary LastAccess timestamp matched an orphan birth to the exact minute; orphans also appeared 2 min after T3 boot at 4:46 AM (including overnight while the machine was idle).
• T3 event log shows zero Antigravity sessions/turns during the flood, and a manual agy --version exits with no orphan, so this is probe-spawn + kill, not sessions and not the binary itself.

#12008 fixed the spawn, but not the leftovers

8c18b5bb2 already stops the probe from spawning and contains session temps under the profile with a start-time sweep. What is still missing: anyone affected before that fix keeps tens of GB of legacy Temp\_MEI* orphans forever. Nothing reclaims them.

Suggestion

One-time safe sweep of legacy orphans: only dirs matching agy markers (agy_acp_licenses.txt / localharness), older than a few days, with no live process in them. Must NOT blanket-delete _MEI*, since other PyInstaller apps use that prefix.

Environment

Windows 11, T3 Code Nightly (build containing the pre-#12008 spawning probe, verified via shipped asar), Antigravity provider enabled, no active Antigravity sessions during the flood.

Start by reviewing commit #12008 (8c18b5bb2) and the T3 server entry point in bin.mjs to locate the existing probe and temp cleanup logic. Implement the suggested Windows sweep for legacy _MEI directories using the stated Antigravity markers, age threshold, and live-process check. Done means affected pre-#12008 leftovers are reclaimed without blanket-deleting other PyInstaller directories.