feat: private checklists for zjazd preparation

Per-user checklists with items that may link a course, reading, deadline,
material or own presentation deck. An item with a reading shares the
reading's read mark. Student API routes with token twins, MCP tools,
migrations, tests and README.

updates/20261030120000_create_jz_bm_checklists.go

@@ -0,0 +1,33 @@
+package updates
+
+import (
+	"github.com/go-gormigrate/gormigrate/v2"
+	"gorm.io/gorm"
+)
+
+// CreateChecklists returns the 20261030120000_create_jz_bm_checklists
+// gormigrate entry: a user's own checklists, e.g. one per zjazd to plan the
+// preparation. They go with the golem15.user user; a deleted zjazd leaves
+// the checklist without one.
+func CreateChecklists() *gormigrate.Migration {
+	return &gormigrate.Migration{
+		ID: "20261030120000_create_jz_bm_checklists",
+		Migrate: func(tx *gorm.DB) error {
+			return execAll(tx, `CREATE TABLE jz_bm_checklists (
+    id BIGSERIAL PRIMARY KEY,
+    user_id INTEGER NOT NULL REFERENCES users (id) ON DELETE CASCADE,
+    meeting_id BIGINT NULL REFERENCES jz_bm_meetings (id) ON DELETE SET NULL,
+    title VARCHAR(255) NOT NULL,
+    description TEXT NULL,
+    sort_order INTEGER NOT NULL DEFAULT 0,
+    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
+);
+CREATE INDEX jz_bm_checklists_user_id_index ON jz_bm_checklists (user_id);
+CREATE INDEX jz_bm_checklists_meeting_id_index ON jz_bm_checklists (meeting_id)`)
+		},
+		Rollback: func(tx *gorm.DB) error {
+			return tx.Exec("DROP TABLE IF EXISTS jz_bm_checklists").Error
+		},
+	}
+}

updates/20261030120100_create_jz_bm_checklist_items.go

@@ -0,0 +1,46 @@
+package updates
+
+import (
+	"github.com/go-gormigrate/gormigrate/v2"
+	"gorm.io/gorm"
+)
+
+// CreateChecklistItems returns the
+// 20261030120100_create_jz_bm_checklist_items gormigrate entry: the items
+// of a checklist. An item may point at a reading, a deadline, a material or
+// a course (the link is cleared when that row goes) and name a deck of
+// golem15.presentations by slug (no foreign key across plugins). done_at is
+// the done mark of an item without a reading; an item with one is done when
+// its owner has read the reading.
+func CreateChecklistItems() *gormigrate.Migration {
+	return &gormigrate.Migration{
+		ID: "20261030120100_create_jz_bm_checklist_items",
+		Migrate: func(tx *gorm.DB) error {
+			return execAll(tx, `CREATE TABLE jz_bm_checklist_items (
+    id BIGSERIAL PRIMARY KEY,
+    checklist_id BIGINT NOT NULL REFERENCES jz_bm_checklists (id) ON DELETE CASCADE,
+    kind VARCHAR(20) NOT NULL DEFAULT 'zadanie'
+        CHECK (kind IN ('lektura', 'artykul', 'ksiazka', 'prezentacja', 'zadanie', 'inne')),
+    title VARCHAR(500) NOT NULL,
+    notes TEXT NULL,
+    url VARCHAR(2048) NULL,
+    course_id BIGINT NULL REFERENCES jz_bm_courses (id) ON DELETE SET NULL,
+    reading_id BIGINT NULL REFERENCES jz_bm_readings (id) ON DELETE SET NULL,
+    deadline_id BIGINT NULL REFERENCES jz_bm_deadlines (id) ON DELETE SET NULL,
+    material_id BIGINT NULL REFERENCES jz_bm_materials (id) ON DELETE SET NULL,
+    presentation_slug VARCHAR(255) NULL,
+    due_at TIMESTAMPTZ NULL,
+    estimate_minutes INTEGER NULL CHECK (estimate_minutes >= 0),
+    sort_order INTEGER NOT NULL DEFAULT 0,
+    done_at TIMESTAMPTZ NULL,
+    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
+);
+CREATE INDEX jz_bm_checklist_items_checklist_id_index ON jz_bm_checklist_items (checklist_id, sort_order);
+CREATE INDEX jz_bm_checklist_items_reading_id_index ON jz_bm_checklist_items (reading_id)`)
+		},
+		Rollback: func(tx *gorm.DB) error {
+			return tx.Exec("DROP TABLE IF EXISTS jz_bm_checklist_items").Error
+		},
+	}
+}