add: WebDL / TVRip media types and filename-token override

Source kind is now declared per-file via a `dvd` / `bluray` / `webdl` /
`tvrip` token in the basename (case-insensitive, word-bounded). Matches
the existing `tt…` / `tvm…` filename convention. When no token is
present, falls back to the pixel-count guess in DetectMediaType, which
still only chooses between DVD and Blu-ray.

The parsed media type drives both ORIGINAL_MEDIA_TYPE in the muxed
metadata and the CRF/preset profile used for encoding. EncodingConfig
gains `webdl` and `tvrip` sub-blocks with conservative defaults
(WebDL 30/3, TVRip 32/2); user can override in config.yaml.

Manual updated with the new tokens, config fields, and pipeline
description.

internal/config/config.go

@@ -61,6 +61,18 @@ func Load(configPath string) (*types.Config, error) {
 	if cfg.Encoding.Bluray.Preset == 0 {
 		cfg.Encoding.Bluray.Preset = 3
 	}
+	if cfg.Encoding.WebDL.CRF == 0 {
+		cfg.Encoding.WebDL.CRF = 30
+	}
+	if cfg.Encoding.WebDL.Preset == 0 {
+		cfg.Encoding.WebDL.Preset = 3
+	}
+	if cfg.Encoding.TVRip.CRF == 0 {
+		cfg.Encoding.TVRip.CRF = 32
+	}
+	if cfg.Encoding.TVRip.Preset == 0 {
+		cfg.Encoding.TVRip.Preset = 2
+	}
 
 	return &cfg, nil
 }