🧑‍💻 Kernel serve CalDAV service on path /caldav/ (#13321)

* 🎨 define the interface of CalDAV

* 🎨 Adjust iCalendar files directory structure

* 🎨 Implement CalDAV Calendar manage functions

* 🎨 Implement CalDAV calendar object manage functions

* 🎨 improve ETag scheme

kernel/go.mod

@@ -22,6 +22,7 @@ require (
 	github.com/denisbrodbeck/machineid v1.0.1
 	github.com/dgraph-io/ristretto v1.0.0
 	github.com/djherbis/times v1.6.0
+	github.com/emersion/go-ical v0.0.0-20240127095438-fc1c9d8fb2b6
 	github.com/emersion/go-vcard v0.0.0-20241024213814-c9703dde27ff
 	github.com/emersion/go-webdav v0.5.1-0.20240713135526-7f8c17ad7135
 	github.com/emirpasic/gods v1.18.1
@@ -154,6 +155,7 @@ require (
 	github.com/shoenig/go-m1cpu v0.1.6 // indirect
 	github.com/shopspring/decimal v1.4.0 // indirect
 	github.com/ssor/bom v0.0.0-20170718123548-6386211fdfcf // indirect
+	github.com/teambition/rrule-go v1.8.2 // indirect
 	github.com/tetratelabs/wazero v1.7.3 // indirect
 	github.com/tklauser/go-sysconf v0.3.14 // indirect
 	github.com/tklauser/numcpus v0.8.0 // indirect

kernel/go.sum

@@ -89,6 +89,7 @@ github.com/dsnet/compress v0.0.1/go.mod h1:Aw8dCMJ7RioblQeTqt88akK31OvO8Dhf5Jflh
 github.com/dsnet/golib v0.0.0-20171103203638-1ea166775780/go.mod h1:Lj+Z9rebOhdfkVLjJ8T6VcRQv3SXugXy999NBtR9aFY=
 github.com/dustin/go-humanize v1.0.1 h1:GzkhY7T5VNhEkwH0PVJgjz+fX1rhBrR7pRT3mDkpeCY=
 github.com/dustin/go-humanize v1.0.1/go.mod h1:Mu1zIs6XwVuF/gI1OepvI0qD18qycQx+mFykh5fBlto=
+github.com/emersion/go-ical v0.0.0-20240127095438-fc1c9d8fb2b6 h1:kHoSgklT8weIDl6R6xFpBJ5IioRdBU1v2X2aCZRVCcM=
 github.com/emersion/go-ical v0.0.0-20240127095438-fc1c9d8fb2b6/go.mod h1:BEksegNspIkjCQfmzWgsgbu6KdeJ/4LwUZs7DMBzjzw=
 github.com/emersion/go-vcard v0.0.0-20230815062825-8fda7d206ec9/go.mod h1:HMJKR5wlh/ziNp+sHEDV2ltblO4JD2+IdDOWtGcQBTM=
 github.com/emersion/go-vcard v0.0.0-20241024213814-c9703dde27ff h1:4N8wnS3f1hNHSmFD5zgFkWCyA4L1kCDkImPAtK7D6tg=
@@ -375,6 +376,7 @@ github.com/stretchr/testify v1.9.0 h1:HtqpIVDClZ4nwg75+f6Lvsy/wHu+3BoSGCbBAcpTsT
 github.com/stretchr/testify v1.9.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
 github.com/studio-b12/gowebdav v0.9.0 h1:1j1sc9gQnNxbXXM4M/CebPOX4aXYtr7MojAVcN4dHjU=
 github.com/studio-b12/gowebdav v0.9.0/go.mod h1:bHA7t77X/QFExdeAnDzK6vKM34kEZAcE1OX4MfiwjkE=
+github.com/teambition/rrule-go v1.8.2 h1:lIjpjvWTj9fFUZCmuoVDrKVOtdiyzbzc93qTmRVe/J8=
 github.com/teambition/rrule-go v1.8.2/go.mod h1:Ieq5AbrKGciP1V//Wq8ktsTXwSwJHDD5mD/wLBGl3p4=
 github.com/tetratelabs/wazero v1.7.3 h1:PBH5KVahrt3S2AHgEjKu4u+LlDbbk+nsGE3KLucy6Rw=
 github.com/tetratelabs/wazero v1.7.3/go.mod h1:ytl6Zuh20R/eROuyDaGPkp82O9C/DJfXAwJfQ3X6/7Y=