feat: get rolling comments

LICENSE

@@ -19,3 +19,6 @@ AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 SOFTWARE.
+
+Methods and logic borrowed from the following programs. See their respective licenses for more details:
+- comment-zouryou (https://github.com/tanbatu/comment-zouryou): Copyright (c) 2022 tanbatu, MIT License

README.md

@@ -84,6 +84,13 @@ download options:
                         download video thumbnail
   -c, --download-comments
                         download video comments
+  --comments-limit N    number of comments to download per thread (default: 1000)
+  --comments-from DATETIME_OR_TIMESTAMP
+                        only download comments posted before a specified time:
+                        - Unix timestamp (e.g., 1686787200)
+                        - ISO 8601 date (e.g., '2023-06-15' → sets to 23:59:59)
+                        - ISO 8601 datetime (e.g., '2023-06-15T14:30:00' or '2023-06-15 14:30:00')
+  --all-comments        request all comments (ignores --comments-limit)
   -e, --english         request video on english site
   --chinese             request video on traditional chinese (taiwan) site
   -aq AUDIO_QUALITY, --audio-quality AUDIO_QUALITY