Overhaul bookmarks/chapters

[OpenFunscripter]

This means replacing the current (lazy) implementation. With a more structured solution.

Bookmarks & Chapters should be exported when saving a *.funscript This will be the starting point https://github.com/Yoooi0/MultiFunPlayer/issues/72#issuecomment-1309585975

[OpenFunscripter]

Todo

• [x] Serialize bookmarks/chapters to funscript
• [x] Deserialize bookmarks/chapters from funscript
• [x] Reimplement the Export clips functionality

When deserializing requires validation that none of the chapters overlap.

[OpenFunscripter]

chapters/bookmarks are written into and read from the metadata object.

"metadata": {
  "bookmarks": [
      {
          "name": "Hello",
          "time": "02:11:25.273"
      },
      {
          "name": "World",
          "time": "05:38:13.103"
      }
  ],
  "chapters": [
      {
          "endTime": "00:05:11.839",
          "name": "A",
          "startTime": "00:00:00.000"
      },
      {
          "endTime": "00:16:14.735",
          "name": "B",
          "startTime": "00:05:11.839"
      },
      {
          "endTime": "00:27:55.654",
          "name": "C",
          "startTime": "00:16:14.735"
      }
  ],
}