plan: filesystem quotas, the half the platform cannot do

Per-user and per-team storage limits need the kernel, not the platform. Members
hold terminal at write and have their own Linux accounts, so a quota counted
through the file browser is decorative — they open a shell and write past it.

The plan is usrquota and grpquota, deliberately not project quotas: every case
here is "this user" or "this team", both already identities the kernel knows,
and a team is already a Linux group. Skipping prjquota also skips the
inode-size trap, since project quotas need 256-byte inodes and cannot be added
to a filesystem that has 128.

Includes the pre-flight that decides whether the procedure applies at all, the
rescue-boot steps, and a throwaway-account test that proves enforcement — because
enabling quotas and setting none looks exactly like success.

The easiest thing to get wrong is recorded prominently: a team folder that is
not setgid charges its files to each member's own group, so the team limit counts
nothing.

For edge-pertento, which is the first real multi-user host and already has one
account. officer-dev will not be multi-user and alpha is the owner's own;
neither needs it.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Officer-Session: 656f5c85-e49a-4f1f-b9f3-042a04b4d043

CLAUDE.md

@@ -537,6 +537,10 @@ explaining why it was safe.
 - `docs/editor-buffer-corruption.md` — an open bug with a trap set for it: background-job output appearing
   inside a file open in the editor. Read it BEFORE investigating a report of that, and before re-testing
   anything it already rules out
+- `docs/filesystem-quotas.md` — **planned, not done**: the host-side half of per-user and per-team storage
+  limits. Why the kernel has to enforce it rather than the platform (members have `terminal` and can write
+  past anything we count), why `usrquota`+`grpquota` and not project quotas, and the one thing easiest to
+  get wrong — a team folder that is not `setgid` charges nothing to the team
 - `TODO.md` — current direction and deferred work; **takes precedence over this file where they disagree**
 - `src/apps/CLAUDE.md` — shared frontend patterns
 - `src/databases/CLAUDE.md` — database patterns