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>

packages/db/src/schema/settings.ts

@@ -25,6 +25,21 @@ export const platformSettings = pgTable(
     primeApiKeyUpdatedAt: timestamp('prime_api_key_updated_at', { withTimezone: true }),
     primeSyncEnabled: boolean('prime_sync_enabled').notNull().default(false),
     primeSyncIntervalMinutes: integer('prime_sync_interval_minutes').notNull().default(30),
+    /**
+     * The Learn share code, in the database because it is rotatable.
+     *
+     * Not an env var and not a constant: rotating it must be something an
+     * administrator does at 11pm when it has been forwarded outside the
+     * company, without a redeploy. Stored in clear rather than hashed because
+     * it is a passphrase a human reads aloud and an admin has to be able to
+     * see it to share it — and because it grants nothing but the platform
+     * track, which is marketing material. It is compared in constant time all
+     * the same; the timing of a wrong answer should not narrow the guess.
+     *
+     * The initial value is a column default so the row is never without one.
+     */
+    learnAccessCode: text('learn_access_code').notNull().default('carlthefog'),
+    learnAccessCodeUpdatedAt: timestamp('learn_access_code_updated_at', { withTimezone: true }),
     updatedByUserId: uuid('updated_by_user_id').references(() => users.id, {
       onDelete: 'set null',
     }),