v0.12.0 — REST API + personal access tokens

A bidirectional API so other apps (Home Assistant, phone shortcuts, scripts,
and the coming MCP server) can read and update the homestead.

- ApiToken model (sha256-hashed, scoped, with prefix/lastUsed/expiry/revoke)
- authenticateRequest() accepts EITHER a NextAuth cookie session OR a Bearer
  PAT; cookie sessions get full access, tokens are limited to their scopes
  (write implies read; resource and global wildcards). ApiError + handleApiError
- Shared service layer (plants/tasks/locations/plant-types) reused by every
  endpoint and, later, the MCP server — logic lives once
- /api/v1: plants (read + add log), plant-types, locations, tasks (read/create/
  complete), and a whoami/discovery root
- Settings → API tokens: create with per-resource read/write checkboxes, raw
  token shown once, revoke; tokens added to backup/restore
- Pure tests for scope matching + token hashing; verified end-to-end (401/403/
  201, lastUsedAt) against a running server

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

prisma/migrations/20260616000002_v0_12_api_tokens/migration.sql

@@ -0,0 +1,24 @@
+-- v0.12.0 — API tokens (personal access tokens for the REST API + MCP)
+
+-- CreateTable
+CREATE TABLE "ApiToken" (
+    "id" TEXT NOT NULL,
+    "name" TEXT NOT NULL,
+    "tokenHash" TEXT NOT NULL,
+    "prefix" TEXT NOT NULL,
+    "scopes" TEXT[],
+    "userId" TEXT NOT NULL,
+    "lastUsedAt" TIMESTAMP(3),
+    "expiresAt" TIMESTAMP(3),
+    "revokedAt" TIMESTAMP(3),
+    "createdAt" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+
+    CONSTRAINT "ApiToken_pkey" PRIMARY KEY ("id")
+);
+
+-- CreateIndex
+CREATE UNIQUE INDEX "ApiToken_tokenHash_key" ON "ApiToken"("tokenHash");
+CREATE INDEX "ApiToken_userId_idx" ON "ApiToken"("userId");
+
+-- AddForeignKey
+ALTER TABLE "ApiToken" ADD CONSTRAINT "ApiToken_userId_fkey" FOREIGN KEY ("userId") REFERENCES "User"("id") ON DELETE CASCADE ON UPDATE CASCADE;