Migrate to SilverBullet v2 indexing system

Replace deprecated query provider with index-based architecture.
Events are now indexed using index.indexObjects() and queryable
via Lua Integrated Query (LIQ).

Breaking changes:
- Plugin now requires SilverBullet v2 (use v0.1.0 for SB v1)
- Old query syntax no longer works (use LIQ instead)
- Manual sync required via 'iCalendar: Sync' command
- Events cached for 6h by default (was real-time)

Co-Authored-By: Claude <noreply@anthropic.com>
Signed-off-by: Alexandre Nicolaie <xunleii@users.noreply.github.com>

deno.jsonc

@@ -1,11 +1,14 @@
 {
   "tasks": {
     "build": "silverbullet plug:compile -c deno.jsonc icalendar.plug.yaml",
+    "build:debug": "silverbullet plug:compile -c deno.jsonc icalendar.plug.yaml --debug",
     "watch": "silverbullet plug:compile -c deno.jsonc icalendar.plug.yaml -w"
   },
   "lint": {
     "rules": {
-      "exclude": ["no-explicit-any"]
+      "exclude": [
+        "no-explicit-any"
+      ]
     }
   },
   "fmt": {
@@ -16,7 +19,7 @@
     ]
   },
   "imports": {
-    "@silverbulletmd/silverbullet": "jsr:@silverbulletmd/silverbullet@^0.10.1",
+    "@silverbulletmd/silverbullet": "jsr:@silverbulletmd/silverbullet@^2.0.0",
     "ts-ics": "npm:ts-ics@1.6.5"
   }
-}
+}