feat(task db): implement a task DB

.dockerignore

@@ -19,3 +19,4 @@
 !/provers/sgx/setup
 !/kzg_settings_raw.bin
 !/core
+!/task_manager

.gitignore

@@ -38,6 +38,13 @@ target/
 # MSVC Windows builds of rustc generate these, which store debugging information
 *.pdb
 
+# SQLite
+# -----------------------------------------------------------------------------------------
+*.sqlite
+*.sqlite-shm
+*.sqlite-wal
+*.sqlite-journal
+
 # Temp files, swap, debug, log, perf, cache
 # -----------------------------------------------------------------------------------------
 *.swp