Rebuild the shell, add Calendar and Learn, and govern reads

Seven parallel agents and an adversarial verification pass. The three things
worth knowing before reading the diff:

RBAC WAS ALREADY BUILT. docs/build-plan.md marks F2 and F3 outstanding and is
stale — packages/core/src/permissions.ts and lib/mutation.ts shipped long ago.
So this does not rebuild them; it closes the gaps an audit found. The big one
is that reads were entirely ungoverned: every GET was "any authenticated
member", so a junior demand rep and a research contractor could both pull
per-block supplier cost and break-even prices from /api/capacity/margin, and
every contract's negotiated terms. For a company whose margin is the business,
that was the hole that mattered. Adds book:read / economics:read / team:read,
a readGuard middleware, and a `viewer` role below member.

THE BUTTON AND THE 403 DISAGREED — the exact thing F3 said must never happen.
Contracts.tsx never called can() at all, so its save button was always enabled
against a server requiring contract:sign; Capacity.tsx gated commitment
creation on deal:write/demand while the server wanted commitment:write/supply.

POST /api/activities was the one write bypassing executeMutation: no capability
check, and any member could mutate accounts.lastActivityAt as a side effect.
It is now a proper mutation() behind activity:write.

The shell becomes three panes — a collapsible shadcn sidebar with an account
switcher on the Piggy accent, a header with real search, and Piggy docked to
the right, page-aware and persistent across navigation. The phone keeps its
bottom tab bar, which is the thing this product already beat trycompai/crm on,
and gains the sidebar as a sheet.

Calendar is a projection over thirteen dated sources rather than a new table,
because a table would duplicate dates that already live on contracts, deals and
commitments and would drift — and one ledger answering the question is the
whole argument. It surfaces export_authorizations and compliance_artifacts,
which had indexed expires_at columns, schema comments saying they must be
alerted on, and no read endpoint or UI anywhere.

Learn carries two tracks. Concepts are members-only; the platform track can be
opened with a share code by someone with no account. The code mints a scoped
learn-only token and never a Principal — every route here resolves a principal
and then checks capabilities, so a principal-minting code would be one missing
check away from leaking the book. "Only platform-track rows may be code-visible"
is a database CHECK constraint as well as a write-path rule, and a test asserts
a valid learn token still gets 401 on /api/dashboard, /api/accounts and
/api/contracts — the same invariant scripts/deploy.sh refuses to ship without.

CD becomes tag-to-ship. CI publishes an image to the Gitea registry on a
release-* tag and cloud-2 pulls it, so no credential on the shared runner can
execute anything on production — by construction rather than by policy. Both
halves of deploy.sh's original rule survive: nothing on the runner reaches the
host, and a human still decides when it ships. deploy.sh gains a rollback and a
public-origin check, and PIG_IMAGE now reaches compose through `sudo env`,
without which sudo's env_reset silently resolved every release to pig:local.

Tests 141 -> 261.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

apps/web/src/index.css

@@ -36,6 +36,39 @@
   --safe-bottom: env(safe-area-inset-bottom, 0px);
   --safe-left: env(safe-area-inset-left, 0px);
   --safe-right: env(safe-area-inset-right, 0px);
+
+  /*
+   * The application header's height, including the notch it sits under. Both
+   * side panes are sticky beneath it and subtract this from the viewport, so
+   * it has to be one number rather than a magic constant in three files.
+   */
+  --app-header-h: calc(3.5rem + var(--safe-top));
+
+  /*
+   * The sidebar primitive's palette.
+   *
+   * Aliases, not values. shadcn's sidebar block wants its own `--sidebar-*`
+   * scale; defining literal colours here would be a second palette to keep in
+   * step with the first, and it would not follow the user's accent — which is
+   * written onto this same element at runtime by lib/theme.tsx. Because these
+   * are HSL channel triples pointing at other HSL channel triples, the dark
+   * theme and every accent flow through for free and there is nothing to
+   * duplicate under [data-theme='dark'].
+   */
+  --sidebar-background: var(--surface);
+  --sidebar-foreground: var(--fg);
+  --sidebar-primary: var(--accent);
+  --sidebar-primary-foreground: var(--accent-on);
+  --sidebar-accent: var(--accent-subtle);
+  --sidebar-accent-foreground: var(--accent-fg);
+  --sidebar-border: var(--border);
+  --sidebar-ring: var(--accent);
+}
+
+@media (min-width: 1024px) {
+  :root {
+    --app-header-h: calc(4rem + var(--safe-top));
+  }
 }
 
 :root[data-theme='dark'] {