caldav leaves the platform

calendar and contacts are a plugin now — plugins/caldav, its own repository like
every other one. a fresh machine runs five processes instead of seven and gets a
calendar by installing one plugin, which is the whole point: the platform stops
carrying a python calendar server for people who may not want one.

what left: the radicale sidecar, four routers, the panel apps, the
dav_app_passwords table, the two screens, the two dock tiles, the permission
registry entry, the settings section, and radicale from every package list.

three platform things had to change first, each committed on its own:
6b5c87da a plugin can be more than one screen; e0df28ff a first-party plugin can
claim a reserved root path. this commit adds the third, `personal` on a plugin
permission — a member granted READ must still mint and revoke their own app
password, because that password is how their own phone reaches their own
calendar. those rows are theirs and nobody else's.

two fixes the work surfaced rather than caused. the dock pinned mountPrefix, so
a multi-screen plugin pinned a tile pointing at /caldav — a route no plugin
serves. and the OPTIONS carve-out was a literal list of four DAV paths; it asks
the claim registry now, so it follows whoever owns the route.

/calendar stays in DEFAULT_DOCK_PATHS. it is installed by default and a fresh
dock that silently dropped it would read as a downgrade.

docs:check earned its keep twice here: it caught spotlight still offering
/settings/integrations/dav-app-passwords after the section was deleted, and the
permission count going 22 -> 21. neither is greppable and both were already wrong
when it ran.

verified against alpha, which is still on the pre-extraction code: /.well-known/
caldav 301s, /dav/ answers 401 with the same WWW-Authenticate realm byte for
byte, /api/caldav/passwords 401s, and OPTIONS reaches the DAV router rather than
being answered as a CORS preflight. installed here end to end — schema applied,
sidecar started, two tiles with their own artwork behind one permission.

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

CLAUDE.md

@@ -212,7 +212,7 @@ ahead of everything, and it re-verifies the token itself so it covers routes tha
 - `permissions/registry.ts` — the single enumeration of what the platform can do, in five kinds:
   `core` (every account, not deniable), `app` (**the grantable surface**), `confined` (grantable, but
   only to an account that has a Linux user), `execution` and `admin` (owner only, and `execution` is
-  never grantable at any level). **22 entries as of 2026-08-24** — verified by `bun run docs:check`, which fails if this number drifts again: 6 core, 3 app, 4 confined, 3 execution, 6 admin (`todos`, the todo board, is the sixth). `notify` moved from `app` to `core` on 2026-08-24: it was grantable, nothing granted it, and every Member's app was silently 403'd registering its own push token. It said 27 for nine days. The execution count dropped by one when Minesweeper became a plugin — see `plugins/minesweeper/manifest.ts` for why that was a fix rather than a downgrade.
+  never grantable at any level). **21 entries as of 2026-08-27** — verified by `bun run docs:check`, which fails if this number drifts again: 6 core, 2 app, 4 confined, 3 execution, 6 admin (`todos`, the todo board, is the sixth). It was 22 until caldav became a plugin and took `calendar` with it — a plugin's permission is registered at runtime from its manifest, so it is real but not in this file's count. `notify` moved from `app` to `core` on 2026-08-24: it was grantable, nothing granted it, and every Member's app was silently 403'd registering its own push token. It said 27 for nine days. The execution count dropped by one when Minesweeper became a plugin — see `plugins/minesweeper/manifest.ts` for why that was a fix rather than a downgrade.
 - `permissions/authorize.ts` — resolves "may this account do this". Owner short-circuits first; every
   other answer is role grants plus core, with `execution`/`admin` stripped even if a row grants them,
   and `confined` stripped for an account with no `osUser`.