Fase B7: CalDAV/CardDAV sync with Nextcloud, and a Calendar view type

- New built-in classes Event and Contact (schema 65.37), plus a
  Calendar View view type alongside table/list/gallery, backed by a new
  fixed month-grid calendar-view component in components/views.cljs
  reusing the existing scheduled/deadline properties.
- New worker/handler/caldav.cljs: a deliberately-scoped CalDAV
  (VEVENT/VTODO) + CardDAV (VCARD) client against a single Nextcloud
  calendar/addressbook collection, with its own minimal iCalendar/vCard
  encoder-decoder and namespace-agnostic multistatus XML extraction
  (no external ical/rrule/xml dependency exists in this project).
- RRULE <-> :logseq.property.repeat/* translation covers only the
  `plus` (advance-from-scheduled) repeat mode with a bare FREQ(;INTERVAL)
  rule -- dotted-plus/double-plus and anything with BYDAY/COUNT/UNTIL
  are left untranslated on purpose rather than mistranslated.
- Credentials live in the platform keychain (save-secret-text!), never
  in the graph. Sync runs Node-only, every 15 minutes per open repo,
  started/stopped alongside the repo's lifecycle in db_core.cljs.
  Conflicts are last-write-wins via ETag: a 412 on push is skipped and
  retried after the next pull refreshes the stored ETag.

deps/db/src/logseq/db/frontend/class.cljs

@@ -115,6 +115,25 @@
      {:title "Area"
       :properties {:logseq.property.class/extends :logseq.class/Page}}
 
+     ;; :logseq.property/scheduled and :logseq.property/deadline (the actual
+     ;; event start/end) are pre-existing baseline properties, not declared
+     ;; here in :schema :properties -- a migrated-in class can only resolve
+     ;; :schema :properties against properties added in that SAME migration
+     ;; step (see `build-initial-classes*`), so a page can still be tagged
+     ;; Event and given scheduled/deadline like any other public property.
+     :logseq.class/Event
+     {:title "Event"
+      :properties {:logseq.property.class/extends :logseq.class/Page
+                   :logseq.property/icon {:type :tabler-icon :id "calendar-event"}}
+      :schema {:properties [:logseq.property.event/location]}}
+
+     :logseq.class/Contact
+     {:title "Contact"
+      :properties {:logseq.property.class/extends :logseq.class/Page
+                   :logseq.property/icon {:type :tabler-icon :id "user"}}
+      :schema {:properties [:logseq.property.contact/email :logseq.property.contact/phone
+                            :logseq.property.contact/organization]}}
+
      ;; TODO: Add more classes such as :book, :paper, :movie, :music)
      )))
 

deps/db/src/logseq/db/frontend/property.cljs

@@ -422,6 +422,36 @@
 
      ;; TODO: Add more props :Estimate, :Cycle, :Project
 
+     :logseq.property.event/location {:title "Location"
+                                      :schema {:type :string
+                                               :public? true}
+                                      :queryable? true}
+     :logseq.property.contact/email {:title "Email"
+                                     :schema {:type :string
+                                              :public? true}
+                                     :queryable? true}
+     :logseq.property.contact/phone {:title "Phone"
+                                     :schema {:type :string
+                                              :public? true}
+                                     :queryable? true}
+     :logseq.property.contact/organization {:title "Organization"
+                                            :schema {:type :string
+                                                     :public? true}
+                                            :queryable? true}
+     ;; CalDAV/CardDAV sync bookkeeping, not user-facing
+     :logseq.property.caldav/uid {:title "CalDAV UID"
+                                  :schema {:type :string
+                                           :hide? true
+                                           :public? false}}
+     :logseq.property.caldav/href {:title "CalDAV Href"
+                                   :schema {:type :string
+                                            :hide? true
+                                            :public? false}}
+     :logseq.property.caldav/etag {:title "CalDAV ETag"
+                                   :schema {:type :string
+                                            :hide? true
+                                            :public? false}}
+
      :logseq.property/icon {:title "Icon"
                             :schema {:type :map}}
      :logseq.property/publishing-public? {:title "Publishing Public?"
@@ -455,7 +485,8 @@
                                           :icon {:type :tabler-icon :id icon}})
                                        [[:logseq.property.view/type.table "Table View" "table"]
                                         [:logseq.property.view/type.list "List View" "list"]
-                                        [:logseq.property.view/type.gallery "Gallery View" "layout-grid"]])
+                                        [:logseq.property.view/type.gallery "Gallery View" "layout-grid"]
+                                        [:logseq.property.view/type.calendar "Calendar View" "calendar"]])
                                  :properties {:logseq.property/default-value :logseq.property.view/type.table}
                                  :queryable? true}
 

deps/db/src/logseq/db/frontend/schema.cljs

@@ -30,7 +30,7 @@
          (map (juxt :major :minor)
               [(parse-schema-version x) (parse-schema-version y)])))
 
-(def version (parse-schema-version "65.36"))
+(def version (parse-schema-version "65.37"))
 
 (defn major-version
   "Return a number.

deps/db/test/logseq/db/frontend/class_test.cljs

@@ -16,6 +16,18 @@
     (is (not (contains? db-class/private-tags :logseq.class/Project)))
     (is (not (contains? db-class/private-tags :logseq.class/Area)))))
 
+(deftest event-and-contact-are-built-in-page-classes
+  (testing "Event and Contact are registered as built-in classes that behave like pages"
+    (is (contains? db-class/built-in-classes :logseq.class/Event))
+    (is (contains? db-class/built-in-classes :logseq.class/Contact))
+    (is (contains? db-class/page-children-classes :logseq.class/Event))
+    (is (contains? db-class/page-children-classes :logseq.class/Contact))
+    (is (not (contains? db-class/private-tags :logseq.class/Event)))
+    (is (not (contains? db-class/private-tags :logseq.class/Contact))))
+  (testing "Event's schema properties only reference properties migrated in the same step"
+    (is (= [:logseq.property.event/location]
+           (get-in db-class/built-in-classes [:logseq.class/Event :schema :properties])))))
+
 (deftest get-class-objects-dedupes-inherited-tags-test
   (let [conn (db-test/create-conn-with-blocks
               {:classes {:Parent {:block/title "Parent"}